042111   SINGH S, JOSHI R, PARDASANI R T (MLV Govt. Coll, Bhilwara - 311 001, Rajasthan, Email: saurabhsingh.chem@gmail.com) : Construction of spiropyrans via [4+2] photocycloaddition reactions and its computational investigation. Indian J Chem Sec B 2020, 59B(08), 1216-24.

[4+2]-Photochemical cycloaddition provides one of the most efficient and versatile route for the exploring of carbocyclic and heterocyclic frameworks of different sizes with high atom economy. [4+2] photocycloaddition of the chalcones (2a-h) obtained by Knoevenagel condensation of thiosatin and different heteroaryl ketones viz. 2-acetyl, 3-acetyl, 4-acetylpyridines and 2-acetylthiophene olefinic 2-chloropropene with as dienophiles led to the construction of six membered novel spiropyran heterocycles (3a-h) with 60 % yield. The mechanism of the [4+2] photocycloaddition reaction has been investigated in detail by DFT-B3LYP/6-31-G+ (2d, 2p) computational method.

3 illus, 7 tables, 24 ref

042110   SINGH G P, ABIRAMI R, GURUNG A (Chemistry Dep, Shri Ramasamy Memorial Univ, Gangtok - 737 102, Sikkim, Email: govind.pratap@gmail.com) : Assessing the effectiveness of different chiral and achiral phosphoric acids in presence of thiourea co-catalyst in co-operative organocatalytic stereoselective glycosylation reactions. Indian J Chem Sec B 2020, 59B(08), 1206-15.

Organocatalytic glycosylation reactions were attempted with an aim to achieve stereoselectivity using chiral TRIP (Binol derived phosphoric acid) and achiral biphenyl phosphoric acids as catalyst and a thiourea derivative as co-catalyst, based on the transition model suggested by Schmidt group[1] during co-operative organocatalysis. Though the stereoselectivity as reported by the Schmidt was not observed, but it was found that the thiourea co-catalyst assisted the catalyst in making the reaction faster, especially in the cases where the catalyst was itself not a strong enough acid.

3 tables, 14 ref

042109   CHOWHAN L R, RAGHAVAN S (Organic Synthesis and Process Chemistry Dep, Indian Institute of Chemical Technology, Hyderabad - 500 007, Email: sraghavan@iict.res.in) : Stereoselective synthesis towards (+)-trans-kumausyne employing vinylogous Mukaiyama type reaction on an α-chloro sulfide. Indian J Chem Sec B 2020, 59B(08), 1199-1205.

A stereoselective synthesis towards (+)-trans-kumausyne is disclosed. The key steps of the synthesis include stereoselective C-C formation employing vinylogous Mukaiyama type reaction of an α-chloro sulfide with 2-trimethylsiloxy furan and base-catalyzed isomerization followed by intramolecular oxa-Michael reaction.

8 ref

042108   WALMIK P (Post-Graduate Studies and Research in Chemistry Dep, Sahyadri Science Coll, Shivamogga - 577 203, Email: prabhakarchavan7@gmail.com) : Synthesis and biological evaluation of novel indolyl-dihydropyridin-3- carboxylate, dihydro[1,2,4]triazol[1,5]pyridin-3-carboxylate and carbohydrazide derivatives. Indian J Chem Sec B 2020, 59B(08), 1191-8.

The present study anticipates the development of novel antioxidant, antimicrobial and antitubercular drugs by using the indole scaffold. Novel indole derivatives, (4a-c), (5a-c) and (6a-i) have been prepared. The structures of all these unknown compounds have been confirmed with the help of elemental analysis, IR, ¹H & ¹³C NMR and mass spectral data. All these previously unknown synthesized compounds screened for their antioxidant, antimicrobial and antitubercular activities. Compound 5a exhibited good RSA 76.58 %, IC₅₀ value <25 µg/mL. Compound 5a exhibited higher absorbance 0.691nm, at concentration 100 µg/mL. Compound 6a showed good metal chelating activity (64.10 %) at a concentration 100 µg/mL. Compound 6a showed potent activity against S. aureus and P. aeruginosa. Compounds 4a and 5a showed promising antitubercular activity MIC 6.25 µg/mL. Compound 6a showed excellent activity (MIC= 3.125 µg/mL) against M. tuberculosis H37Rv, than the standards pyrazinamide (MIC= 3.125) and Streptomycin (6.25 µg/mL).

5 tables, 40 ref

042107   MOHAMADPOUR F (Apadana Institute of Higher Education, Shiraz, Iran, Email: mohamadpour.f.7@gmail.com) : Potassium alum as a naturally mineral and economical catalyst for the one-pot, multi-component and clean synthesis of 2-oxo(thio)-1,2,3,4-tetrahydropyrimidines and N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates. Indian J Chem Sec B 2020, 59B(08), 1183-90.

An environmental friendly synthetic route for potassium alum catalyzed one-pot multi-component synthesis of biologically active 2-oxo(thio)-1,2,3,4-tetrahydropyrimidines and N--aryl-3-aminodihydropyrrol-2-one-4-carboxylates has developed. The present synthetic route has the notable advantages of natural, mineral, inexpensive and non-toxic catalyst, mild reaction conditions, eco-friendly, one-pot and good to high yield of biological active products. This method is simple for work up and the compound formed filtered and purified just by simple crystallization.

8 tables, 36 ref

042105   SINGH V D, UPPAL A, KAMNI, KHAJURIA Y, SRINIVASAN R, NARAYANA B, SAROJINI B K, ANTHAL S, KANT R (Physics Dep, Jammu Univ, Jammu Tawi - 180 006, Email: rkant.ju@gmail.com) : Synthesis, FT-IR, UV-VIS, DFT studies and SCXRD structure of 1-(tert-butyl) 3- ethyl-3-(hydroxy(thiophen-2-yl)methyl)piperidine-1,3-dicarboxylate. Indian J Chem Sec B 2020, 59B(07), 1043-56.

The crystal structure of 1-(tert-butyl) 3-ethyl 3-(hydroxy(thiophen-2-yl)methyl)piperidine-1,3-dicarboxylate (C₁₈H₂₅NO₅S) I has been determined by Single Crystal X-ray Diffraction (SCXRD) techniques. It crystallizes in the orthorhombic space group Pca2₁ with unit cell parameters a = 19.4502(13)Å, b= 6.3571(4)Å, c= 15.2577(10) Å and number of molecules per unit cell, z = 4. The intensity data have been collected at room température (293 K) and the structure has been solved by direct methods. The full matrix least-squares refinement has converged the final R-value to 0.035 for 2251 observed reflections. The piperidine ring adopts a chair conformation. The structure is stabilized by two C–H…O (intermolecular interactions) and five C–H…O (intramolecular interactions). The structural and spectral studies of 1-(tert-butyl) 3-ethyl 3-(hydroxy(thiophen-2-yl)methyl)piperidine-1,3-dicarboxylate have been carried out by using both experimental and quantum chemical techniques.

9 illus, 12 tables, 46 ref

042104   PRASAD J, KUMAR M, PANDAY S K (Applied Chemistry Dep, M. J. P. Rohilkhand Univ, Bareilly, Uttar Pradesh - 243 006, Email: skpandey@mjpru.ac.in) : Asymmetric synthesis of 2,4,5- substituted prolines through 1,3-dipolar addition reaction of N-arylidene menthyl esters of α-aminoacid with methyl acrylate. Indian J Chem Sec B 2020, 59B(07), 1039-42.

Proline and its derivatives constitute the important organic entities as organocatalyst, ACE inhibitors, bioactive molecules/intermediates to bioactive molecules as well as components of various natural products e.g. Kainic acid, (-)-domoic acid, etc. Due to its wide range of utility extensive studies have been made for the synthesis of 2, 3, 4 or 5 substituted prolines. One pot synthesis of 2,4,5-substituted prolines through 1,3-dipolar addition of various amino acids with homochiral acrylate has also been carried out successfully. Herein we wish to report the 1,3-dipolar addition of Schiff bases, where chiral auxiliary has been introduced in the Schiff bases and 1,3dipolar addition with methyl acrylate leading to the synthesis of 2(S),4(S),5(R)-substituted prolines has been achieved successfully.

29 ref

042103   MOHAMADPOUR F (Apadana Institute of Higher Education, Shiraz, Iran, Email: mohamadpour.f.7@gmail.com) : An eco-safe and solvent-free approach for clean and one-pot synthesis of 3,4-dihydropyrimidin-2-(1H)-one/thione derivatives using Zn(OAc)₂.2H₂O as an environmental friendly, readily and efficient catalyst. Indian J Chem Sec B 2020, 59B(07), 1030-8.

An environmental friendly, economical and clean Biginelli approach in presence of readily available zinc acetate dihydrate (Zn(OAc)₂.2H₂O) to access biologically active 3,4-dihydropyrimidin-2-(1H)-ones/thiones derivatives via one-pot, three-component reaction of β-keto esters (methyl or ethyl acetoacetate), aromatic aldehyde (benzaldehye derivatives) and urea or thiourea in high to excellent yields has been studied. This solvent-free procedure is sustainable and advantageous compared to conventional methods due to short reaction times, one-pot procedure, easy handling, efficient, environmentally benign nature, low-cost and non-toxic catalyst, eco-friendly, ready availability of starting materials and no requirement of chromatographic purification. The products have been characterized by melting points and ¹H NMR spectroscopy.

4 tables, 32 ref

042102   JAIN S, MAIDH T, BADOLE M (Chemistry Dep, Ramnarain Ruia Autonomous Coll, Mumbai - 400 019, Email: swareena1@gmail.com) : Enhanced reaction rate by using N,N-dimethylformamide as a catalyst in Knoevenagel condensation. Indian J Chem Sec B 2020, 59B(07), 1025-9.

The method of microwave-assisted synthesis of benzylidenemalononitrile and its derivatives by using N,N-dimethylformamide as the catalyst is found to be a superior alternative to the conventional method of synthesis. While the conventional methods in recent times have taken from several hours to a few minutes and produce an average yield, herein is reported the realization of a very similar reaction in comparatively much shorter time of a few seconds, producing a high yield. The products are characterized using infrared and nuclear magnetic resonance spectroscopy.

1 illus, 1 table, 25 ref

042101   KANTHARAJU K, HIREMATH P B (Chemistry Dep, Rani Channamma Univ, Belagavi - 591 156, Email: kk@rcub.ac.in) : CuI-NPs catalyzed mechanochemical-assisted N-Boc protection of organic amines. Indian J Chem Sec B 2020, 59B(07), 1016-24.

A simple, solvent-free, faster and mechanochemical approach for the N-tert-butoxycarbonylation of amines catalyzed by copper iodide nanoparticles as a recyclable catalyst is described. The advantages of this method are simplicity, shorter reaction time (5–15 min), a cost-effective catalyst, and excellent product isolation (82-92 %). N-Boc protection of various structurally diverse aliphatic, aromatic, and heterocyclic amines have been carried out with (Boc)₂O with 10 mol % catalyst under pestle mortar grinding under solvent-free conditions. The catalyst possesses distinct advantages, ease of handling as well as removal, cleaner reactions, high activity, and environmentally benign. The final product has been characterised by various spectroscopic techniques.

3 illus, 3 tables, 54 ref

042100   HIREMATH P B, KANTHARAJU K (Chemistry Dep, Rani Channamma Univ, Belagavi - 591 156, Email: kk@rcub.ac.in) : Zinc dust catalysed efficient synthesis of 4-arylidene-2-phenyl-5(4H)-oxazolones. Indian J Chem Sec B 2020, 59B(07), 1010-5.

A straight forward synthesis of 4-arylidene-2-phenyl-5(4H)-oxazolones (also called azlactones) by the condensation of arylaldehyde with hippuric acid in the presence of acetic anhydride and zinc dust as aheterogeneous catalyst is described. The reaction proceeds rapidly, does not require any additives and has a significantly shorter reaction rate. In the present method, aromatic aldehydes and hippuric acid have been successfully applied to synthesize various substituted azlactones in good to excellent yields. The final product has been characterised by FT-IR, ¹H and ¹³C NMR, and mass spectrometry.

1 illus, 3 tables, 67 ref

042099   BEGUM S, RAJESWARI B U, ZEHRA A, TIWARI A K, PRAKASHAM R S, RAJU B C (Organic Synthesis & Process Chemistry Dep, CSIR-Indian Institute of Chemical Technology, Hyderabad - 500 007, Email: chinaraju@iict.res.in) : Condensation of nicotinaldehydes with acetophenones and NH₄OAc: A convenient synthesis and biological activities of 2',6'-diphenyl-3,4'-bipyridines. Indian J Chem Sec B 2020, 59B(07), 1001-9.

2',6'-Diphenyl-3,4'-bipyridines 3a-t have been achieved by the three-component, one-pot reaction of nicotinaldehydes 1a-b, acetophenones 2a-j and anhydrous ammonium acetate under solvent free conditions at 120°C. All the prepared compounds 3a-t have been screened for anti-microbial, free-radical scavenging and α-glucosidase inhibitory activities. Compounds 3m-r have shown anti-bacterial activity and compounds 3m-n identified as anti-fungal agents. Compounds 3d, 3h, 3m and 3r-s have shown α-glucosidase inhibitory activity.

3 tables, 11 ref

042097   SRINIVAS A, SUNITHA M, KARTHIK P, REDDY K V (Chemistry Dep, Vaagdevi Degree & PG Coll, Kishanpura, Warangal - 506 001, Email: avula.sathwikreddy@gmail.com) : Synthesis and biological evaluation of novel phosphonyl thiazolo pyrazoles. Indian J Chem Sec B 2020, 59B(06), 867-76.

A series of novel dimethyl 7-((2S,3S)-3-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-3,6-dihydro-2H-pyran-2-yl)-4-(4-fluorophenyl)-9-oxo-8-phenyl-6-thia-1,2,8-triazaspiro[4.4]non-2-en-3-ylphosphonate 11a-g have been synthesized by the reaction of chalcone derivatives of (E)-5-benzylidene-2-((2S,3S)-3-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-3,6-dihydro-2H-pyran-2-yl)-3-phenylthiazolidin-4-one 10a-g with Bestmen Ohira reagent. The chemical structures of newly synthesized compounds have been elucidated by IR, NMR, MS and elemental analysis. The compounds 11a-g have been evaluated for their nematicidal activity against Dietylenchus myceliophagus and Caenorhabditis elegans. Compound 11b, 11c, 11g and 11f show appreciable nematicidal activity.

2 tables, 46 ref

042096   DEVI T R, LAXMINARAYANA E, CHARY M T (Jawaharlal Nehru Technological Univ Hyderabad, Kukatpally, Hyderabad - 500 085, Email: mtcharya@yahoo.com) : Synthesis, biological evaluation and docking studies of (4-aryl-3-methyl-4,5- dihydropyrazolo[3,4-c]pyrazol-1(3aH)-yl)(3-hydroxyquinoxalin-2-yl)methanones. Indian J Chem Sec B 2020, 59B(06), 862-6.

An efficient synthesis of (4-aryl-3-methyl-4,5-dihydropyrazolo[3,4-c]pyrazol-1(3aH)-yl)(3-hydroxyquinoxalin-2-yl) methanones is described via reactions of ethyl acetoacetate with 3-hydroxyquinoxaline-2-carbohydrazide. The structures of the compounds prepared have been determined by spectral analyses.

3 illus, 2 tables, 10 ref

042094   RAO S L, VEERABHADRASWAMY M, MOLKERE B B (P E S Univ, Bengaluru - 560 085, Email: vbs@pes.edu) : An effortless microwave synthesis of N-(aryl) substituted benzamides under solvent free conditions. Indian J Chem Sec B 2020, 59B(06), 850-5.

Benzamides and substituted benzamides are versatile compounds used in a range of pharmacological and biological active intermediate chemicals for conversion to fine chemicals. The current syntheses protocols are chemical and energy intensive. Herein is present an effortless solvent free microwave assisted synthesis of twenty N-(aryl)-substituted benzamides having good to excellent yields with short reaction time, high selectivity and occurring under milder conditions with high atom efficiency. The structures of the prepared compounds have been confirmed using melting point, FT-IR, ¹H and ¹³C NMR spectral data which are in good agreement with the previously reported literature. Unlike conventional methods, the present novel process protocol offers cleaner, greener technologies in which effluent streams are minimized.

1 illus, 1 table, 16 ref

042093   NAKKALWAR S L, KASRALIKAR H M, KAMINWAR N S, PATWARI S B, JADHAV V B (Chemistry Dep, L. B. S. Mahavidyalaya, Dharmabad 431 809, Nanded, Email: viveka22@gmail.com) : A green synthesis of isoquinolines using Ru(II)/PEG-400 as homogeneous recyclable catalyst via C-H/N-N bond activation. Indian J Chem Sec B 2020, 59B(06), 842-9.

A novel and green synthesis of 1-phenyl isoquinoline derivatives has been developed by using Ru(II)/PEG-400 as homogeneous recyclable catalyst via C-H/N-N bond activation via C-H/N-N functionalization of 1-(diphenylmethylene) hydrazine and aryl substituted acetylenes. In order to realize the proposed protocol, Cu(OAc)₂ and AgSbF₆ are used as oxidant and additive respectively in PEG-400 biodegradable solvent. This protocol has a simple extraction procedure, uses biodegradable solvent, affords high atom economy, employs a reusable catalytic system, provides wide substrate scope with high yield of product, for the synthesis of isoquinoline derivatives.

3 tables, 19 ref

044040   ANUSHA A M , SHERENA P A , ANNAMALA P T, MUKKADAN J K (Biochemistry Dep, Jubilee Mission Medical Coll, Thrissur, Kerala, Email: drannamala@gmail.com) : Screening of sixteen commonly consumed green leafy vegetables for carotenoids. Int J Med Res Health Sci 2020, 9(12), 79-88.

Carotenoids can act as an antioxidant, anti-inflammatory, and anticancer agents. Important bioactive carotenoids are present in green leafy vegetables, which form part of dietary ingredients. The present study is aimed at screening sixteen commonly consumed green leafy vegetables for the distribution of carotenoids. Methods: Sixteen green leafy vegetables-curry leaves (Murraya koenigii), fenugreek (methi) leaves (Trigonella foenum-graecum), coriander leaves (Coriandrum sativum), broccoli leaves (Brassica oleracea), bay leaves (Laurus nobilis), oregano leaves (Origanum vulgare), marjoram leaves (Origanum majorana), basil leaves (Ocimum basilicum), pandan leaves (Pandanus amaryllifolius), sage leaves (Salvia officinalis), thyme leaves (Thymus vulgaris), lemon grass (Cymbopogon citratus), kaffirlime leaves (Citrus hystrix) and parsley leaves (Petroselinum crispum) were dehydrated, and carotenoids were extracted and analysed by HPLC. Of the leaves analyzed, curry leaves, coriander leaves, and fenugreek leaves were found to be rich sources of carotenoids. These findings suggest that curry leaves, coriander leaves, and fenugreek leaves are rich in carotenoids and can be used for the preparation of carotenoid-rich extracts for studying antioxidant, anti-inflammatory, and anticancer activities.

20 illus, 1 table, 15 ref

042092   CHAKRABORTY M (Chemistry Dep, Government Girls’ General Degree Coll, Kolkata - 700 023, Email: mumu_chak@yahoo.com) : Reactions of the carbazole alkaloid Mahanimbine with mineral acid, lewis acid and m-chloroperbenzoic acid. Indian J Chem Sec B 2020, 59B(06), 837-41.

Mahanimbine, a C₂₃ carbazole alkaloid, has been isolated from the leaves of Murraya koenigii Spreng. This carbazole alkaloid, with a C₅H₉ ring residue, on reaction with different acids shows some interesting results. Structures of the naturally occurring compound as well as the synthetic products have been ascertained on the basis of 1D and 2D NMR spectroscopic data. In this paper is discuss isolation, structure elucidation and some chemical transformations of mahanimbine on reaction with mineral acid, Lewis acid and m-chloroperbenzioc acid.

1 illus, 2 tables, 11 ref

042091   AHMAD A, TIWARI S (Chemistry Dep, Allahabad Univ, Allahabad - 211 002, Uttar Pradesh, Email: drshailendratiwariau@gmail.com) : A one pot, efficient and eco-friendly synthesis of 1,3,4-thiadiazolo[3,2-a] pyrimidine scaffold via Aza–Michael addition and intramolecular cycloelimination reactions in poly ethylene glycol (PEG). Indian J Chem Sec B 2020, 59B(05), 724-729.

Potassium carbonate in poly (ethylene glycol-400) has been found to be a highly effective and efficient medium for the straight forward, convenient, one pot and green synthesis of ethyl 2-substituted phenyl-7-oxo-7H-[1,3,4]- thiadiazolo [3,2-a]- pyrimidine-6-corboxylate and -6-corbonitrile through intramolecular cyclo-elimination of Michael adducts formed between the reaction of 2-amino-5 substituted thiadiazoles with diethyl-2- (ethoxymethylene) malonate and ethyl-2- cyano-3-ethoxyacrylate respectively. The structures of all the new compounds have been elucidated using IR, ¹H and ¹³C NMR, mass spectral data and elemental analyses.

2 tables, 40 ref

042089   JOSHI P, MAHAJAN D, CHEJARA D (Chemistry Dep, Government Science Coll, Vankal, Surat - 394 430, Email: mahajandh@gmail.com) : Facile synthesis and characterization of some new 5-arylidene-thiazolidine-2,4- diones and their antimicrobial evaluation. Indian J Chem Sec B 2020, 59B(05), 710-5.

A series of novel 5-arylidene-thiazolidine-2,4-diones derivatives have been synthesized by the Knoevenagel condensation of aromatic aldehydes and N-substituted thiazolidinedione-2,4-diones. Use of KAl(SO₄)₂•12(H₂O) i.e. Alum for the reaction makes this synthesis facile because of several advantageous factors viz. non-toxicity, efficient catalytic ability and cheap cost of alum. Substitution of arylidene moiety at the position 5 on the thiazolidine-2,4-diones nucleus has occured using this facile approach. Synthesized derivatives have been characterized using various analytical tools and antimicrobial evaluation thereof has been performed against Gram-positive, Gram negative bacteria and a fungal strain. All synthesized compounds show moderate to very good activity against the microorganisms that they have been tested against.

3 tables, 20 ref

042086   VARIYA H H, PANCHAL V, PATEL G R (Chemistry Dep, Sheth M. N. Science Coll, Patan - 384 265, Gujarat, Email: hirenvariya9@yahoo.com) : Synthesis, anti-tuberculosis and anti-bacterial activities of sulfonamide bearing 4-((2-(5-bromo-1H-pyrazolo[3,4-b]pyridin-1-yl)-2-oxoethyl)amino)-N-(various substitutions)benzenesulfonamide. Indian J Chem Sec B 2020, 59B(05), 682-9.

In this study all the new synthesized compounds of sulfonamide bearing 4-((2-(5-bromo-1H-pyrazolo[3,4-b]pyridin-1-yl)-2-oxoethyl)amino)-N-(various-substitutions)benzenesul-fonamide have been synthesized by using 1-(5-bromo-1H-pyarazolo[3,4-b]pyridin-1yl)-2-chloroethanone which has been fused with various sulfa drugs in presence of potassium carbonate and DMF. All the derivatives have been recognized by physical properties like melting point and characterization by elemental analysis (CHNS) and various spectral techniques such as FT-IR, ¹H and ¹³C NMR, and ESI-MS. The series of these pyrazolo[3,4-b]pyridin bearing sulfonamide have been synthesized and the final derivatives have been evaluated for bioactivity such as anti-bacterial activity against gram +ve and gram −ve and also screened for their in vitro anti tubercular activity against Mycobacterium tuberculosis H₃₇RV. The results for the synthesized compounds have been compared against standard drugs.

3 illus, 4 tables, 25 ref

042085   KADAM H K, GAWAS A L, VERNEKAR S S, CHODANKAR A A, GAONKAR S S, SALGAONKAR L N, ANVEKAR T S, VAZ T, MHALDAR S N (Chemistry Dep, St. Xavier’s Coll, Mapusa, Goa - 403 507, Email: harikadam05@gmail.com) : Pivalic acid assisted Biginelli reaction for synthesis of dihydropyrimidinones and dihydrothiopyrimidinones. Indian J Chem Sec B 2020, 59B(05), 677-81.

Herein is provided an alternate, simple, multigram scale, efficient route for Biginelli reaction for synthesis of dihydropyrimidinones using urea, ethylacetatoacetate, and benzaldehyde with pivalic acid.

2 illus, 2 tables, 34 ref

042082   BANERJI A, GHOSH A, BANERJI J, PRANGE T, RAO M M (Central Ayurveda Research Institute for Drug Development, Bidhannagar, Kolkata - 700 091, Email: ablabcu@yahoo.co.uk) : [3+2] Cycloadditions. Part XXXIII. Selective cycloadditions of C-(1-naphthyl)-N-methyl nitrone and C-phenyl-N-benzyl nitrone to α,β-unsaturated carbonyl compounds^1,2. Indian J Chem Sec B 2020, 59B(04), 488-501.

[3+2] Cycloadditions [32CA] involving nitrones as 1,3-dipolar species to alkenes yield isoxazolidines, which on further transformations can be converted to naturally occurring bioactive compounds. Thus the 32CA route provides conversion of simple natural products to more complex natural occurring bioactive nitrogen heterocycles, and close analogues. The present work deals with 32CA between the nitrones C-(1-naphthyl)-N-methyl nitrone and C-phenyl-N-benzyl nitrone to α,β-unsaturated carbonyl compounds as dipolarophiles, viz. arylidene malonate esters, methyl cinnamate and benzylidene acetophenone (chalcone). Methyl cinnamate is a naturally occurring compound, while the chalcone scaffold is present in several natural products. Structure elucidation of the generated cycloadducts have been achieved by means of detailed spectroscopic and XRD studies. All the cycloadditions investigated occurr regioselectively to yield tetra/penta-substituted isoxazolidines, where the carbonyl group(s) are situated at the 4-position of the isoxazolidine ring. DFT computations including optimised geometries, FMO energies, electronic chemical potentials, chemical hardness, chemical softness and reactivity indices of a number of the reactants have been calculated at DFT/B3LYP/6-31++G(d,p) level of theory. The calculated reactivity indices have been used to analyse the 32CAs studied and to predict the regioselectivities; the predictions are in excellent accord with the experimental results.

7 illus, 3 tables, 24 ref

042081   SRIVASTAVA K, LAKHMANI D, SRIVASATAVA J, SINGH R B (Shri Ramswaroop Memorial Univ, Barabanki, Uttar Pradesh - 225 003, Email: krishna.cy@srmu.ac.in) : Synthesis and characterization of new thiazole involving isatin for studying their antimicrobial activity. Indian J Chem Sec B 2020, 59B(04), 485-7.

1-(Substituted-1-ylmethyl)indoline-2,3-dione 1a-c have been synthesized from different types of secondary amine with isatin and formaldehyde in alcohol. The compound 1 have then been converted to the respective compound 2a-g (Z)3-(4-subsitutedphenylimino)-1-(substituted-1-ylmethyl)indolin-2-one by treatment with different types of primary amines. Interaction of compound 2 with thioglycolic acid and chloro acetyl chloride results in cyclization to give compound spiro isatin derivatives compounds 3a-g. The anti-microbial activity screening of novel spiro isatin substituted compounds have also been carried out.

2 tables, 16 ref

042080   VENEPALLY V, SIRISHA K, KUMAR C G, JALA R C R (CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad - 500 007, Email: jrcreddy10@gmail.com) : Synthesis and antimicrobial evaluation of novel alkylated piperazine-based fluoroquinolone carboxylate derivatives. Indian J Chem Sec B 2020, 59B(04), 474-84.

In the present study, to synthesize quinolone-piperazine alkylated analogues, initially 3,4-difluoro nitro benzene is reduced to yield 3,4-difluorobenzenamine which is treated with diethyl ethoxymethyl enemalonate to yield diethyl 2-((3,4-difluorophenylamino) methylene) malonate. This has been further cyclized to produce ethyl 6,7-difluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate which is treated with iodoethane to produce ethyl 1-ethyl-6,7-diifluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate. This is hydrolyzed and subsequent nucleophilic substitution with piperazine at 7th position gives quinolone-piperazine derivative. This is alkylated to yield 1-ethyl-6-fluoro-7-(4-alkylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid which is treated with ethanol to afford the desired ethyl 1-ethyl-6-fluoro-7-(4-hexylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylate derivatives. Based on the antimicrobial activity studies, hexyl analog 8a exhibits potent antimicrobial activity against Staphylococcus aureus MTCC 96, Bacillus subtilis MTCC 121, Micrococcus luteus MTCC 2470 (MIC value 1.9µg/mL), with respect to other synthesized compounds and reference drug ciprofloxacin. 8b (heptyl analogue) and 8c (nonyl analogue) show significant activity with MIC value 3.9µg/mL. In the case of antifungal screening, 8a, 8b and 8c show significant antifungal activity against Candida albicans MTCC 3017with MIC value ranged from 3.9 to 7.8µg/mL. Compounds 8a (butyl) shows potent minimum bactericidal concentration activity with MIC value 3.9µg/mL against the tested strains.

3 tables, 34 ref

042079   VIJAYENDAR V, ROUTHU S R, KUMAR C G, JALA R C R (CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad - 500 007, Email: jrcreddy10@gmail.com) : Synthesis, cytotoxic evaluation of novel 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4- oxadiazole and 2-alkyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole derivatives. Indian J Chem Sec B 2020, 59B(04), 465-73.

Interest in the biological applications of oleochemicals has resulted in the development of new heterocyclic compounds from the fatty acids which are renewable raw materials. In the present study the synthesis of hybrid compounds by involving fatty acids, indole-3-acetic acid (heteryl) and trimethoxy benzoic acid (aryl) to derive 2, 5-substituted 1,3,4-oxadiazole moiety using molecular hybridization approach has been carried out. A series of novel 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4-oxadiazoles 4a-j and 2-alkyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole 8a-j analogues have been synthesized and evaluated for their cytotoxicity against A549, MCF-7 and HeLa cell lines. Almost all the tested compounds reveal cytotoxicity against all the cell lines, especially 2-((1H-indol-3-yl) methyl)-5-alkyl-1,3,4-oxadiazoles based compounds (4c, 4d, 4e) which display potent inhibitory activity with IC₅₀ values ranging between 8.26 to 11.36 μM.

1 table, 35 ref

042078   SHIROLE G D, TAMBE A S, SHELKE S N (Chemistry Dep, Dada Patil Mahavidyalaya, Karjat - 414 402, Email: gdshirole@gmail.com) : Ionic liquid catalyzed one pot green synthesis of isoxazolone derivatives via multicomponent reaction. Indian J Chem Sec B 2020, 59B(04), 459-64.

A series of 3-methyl-4-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)isoxazol-5(4H)-one derivatives have been efficiently synthesized by environmentally benign, one-pot three component condensation of substituted 1,3-diaryl-1H-pyrazole-4-carboxyaldehyde, β-keto ester and hydroxyl amine hydrochloride in the presence of ionic liquid [HNMP][HSO₄] as a catalyst in ethanol. These derivatives have been synthesized by conventional, ultrasound and microwave irradiation methods. The combination of ionic liquid with ultrasound as well as microwave irradiation makes the protocol fascinating and environmentally benign. In addition, it has several benefits such as simple work-up procedure, clean reaction profile, short reaction time and good yields.

1 illus, 2 tables, 60 ref

042077   KUMAR P V, REDDY K M, RAO V R (Chemistry Dep, National Institute of Technology, Warangal - 506 009, Email: vrajesh@yahoo.com) : Synthesis of some 3-(2-substituted sulfanyl-imidazo [2,1-b][1,3,4] thiadiazol-6- yl)-chromen-2-one and its derivatives. Indian J Chem Sec B 2020, 59B(04), 454-8.

A series of 3-(2-substituted sulfanyl-imidazo [2,1-b][1,3,4] thiadiazol-6-yl)-chromen-2-ones (3) have been synthesized from 3-(2-bromo acetyl) chromen-2-ones 1 and 2-amino-5-thio substituted[1,3,4]thiadiazole 2 in anhydrous ethanol. The 7,8-benzo analogs of 3-(2-substituted sulfanyl-imidazo[2,1-b][1,3,4] thiadiazol-6-yl)-chromen-2-ones 5 have been synthesized under similar conditions. All the synthesized compounds have been characteriszed by analytical and spectral data.

1 illus, 17 ref

042075   OMER R A, AHMED L O, KOPARIR M, KOPARIR P (Chemistry Dep, Koya Univ, Kurdistan Region – F.R. Iraq, Email: rebaz.anwar@koyauniversity.org) : Theoretical analysis of the reactivity of chloroquine and hydroxychloroquine. Indian J Chem Sec A 2020, 59A(12), 1828-34.

Chloroquine (CQ) and Hydroxychloroquine (HCQ) have a low safety margin and its toxic effects are closely related to the ingested dose. Both drugs were tested for reactivity under different conditions but still need to be understood. A thermodynamic and kinetic study with control the electronic properties also show the reaction of the molecule. In this study, theoretical calculations have been performed using Density Functional Theory (DFT) and Hartree-Fock (HF) to find the band gap energy and determine a suitable basis set. A computation based on B3LYP level was accomplished to obtain the geometrical structures for both CQ and HCQ molecules. Based on the B3LYP/6-31G(d,p) basis set, DFT measurements of frontier molecular orbitals and molecular electrostatic potentials have been implemented for both CQ and HCQ. The atomic charge distribution of nitrogen and oxygen is calculated for CQ and HCQ using DFT and HF on a basis set 6-31G**. Ab initio DFT with HF at 6-31G** basis set is performed for thermodynamic analysis for both CQ and HCQ structures.

4 illus, 5 tables, 32 ref

042074   LIU H, HAN H-Y, LIU M-H, ZHAO Y-F (Zhengzhou Normal Univ, Zhengzhou, Hena 450044, China, Email: lhzznu@163.com) : A sensitive electrochemical sensor for cryptotanshinone based on electrochemical reduced graphene oxide and carbon nanotube composite film modified glassy carbon electrode. Indian J Chem Sec A 2020, 59A(12), 1822-7.

The electrodeposition of reduced graphene oxide and carbon nanotube (ErGO/CNTs) composite film modified electrode has been fabricated by electrochemical reduction of graphene oxide (GO) and MWNTs composite film coated on the surface of glassy carbon electrode (GCE). The results show that in 0.2 mol/L NaAc-HAc (pH= 4.5) buffer solution, cryptotanshinone produced a pair of sensitive redox peaks with peak potentials of -0.180 V and -0.207 V (vs SCE). The electrode reaction was two electrons and two protons participate in the completely reversible process of adsorption control. The ErGO/CNTs membrane modified electrode has obvious catalytic and sensitizing effects on the redox of cryptotanshinone. Differential pulse voltammetry (DPV) is used to investigate the relationship between oxidation peak current and cryptotanshinone concentration. It is found that the oxidation current of cryptotanshinone is linear with its concentration in the range of 2.7 × 10^-8 ~1.3 × 10^-5 mol/L and the determination limit is 1.0 × 10^-8 mol/L, which can realize the electrochemical detection of cryptotanshinone in the drug.

7 illus, 1 table, 22 ref

042073   DAVE P, BHAGAT B, AGRAWAL B, MAITY P (Gujarat Forensic Sciences Univ, Gandhinagar - 382 007, Gujarat, Email: pmaity@gfsu.edu.in) : A supramolecular strategy for ratiometric luminescence sensing of nitroaromatic explosives in water. Indian J Chem Sec A 2020, 59A(12), 1814-21.

In the present work we have demonstrated a supramolecular approach for ratiometric luminescence sensing of nitroaromatic explosive compounds (NAEs) by employing a red luminescent Eu(III) complex and a green luminescent Pt(II) complex with in a Triton X-100 surfactant based micellar host in water. The Eu-complex gets entrapped inside micellar core whereas the Pt-C2 remains grafted on the surface of the spherical micelles due to their structural amendments and thus facilitates preferential interaction of Pt-C2 with NAE molecules mainly through π-π interaction. The presence of explosive traces quenches the green emission (508-545 nm) of Pt-complex whereas the red emission (614 nm) of Eu-complex remains unaffected. The strategy demonstrates first report of two independent luminophore based ratiometric sensing in water using a micellar host.

6 illus, 1 table, 32 ref

042072   THAKUR S R, BEHURA R, BEHERA S, SAYALA R B, BARICK A K, RAMAKRISHNA D S, JALI B R (Chemistry Dep, Veer Surendra Sai Univ of Technology, Sambalpur - 768 018, Odisha, Email: bigyan.Jali7@gmail.com) : Selective detection of fluoride and hydrogen sulfate anions by pyrimidine-based fluorescence chemosensor. Indian J Chem Sec A 2020, 59A(12), 1809-13.

The binding and sensing abilities of pyrimidine based fluorescence chemosensor L towards different anions such as F^-, Cl^-, Br^-, I^-, NO₃^-, ClO₄^-, H₂PO₄^- and HSO₄^- have been examined by fluorescence spectroscopy in DMSO-H₂O (7: 3, v/v). Upon successive addition of various anions to DMSO-H₂O solutions of L; quenching in emission fluorescence is observed at 480 nm. Analysis of fluorescence emission changes suggested the formation of 1:1 complex of L with the anions. From the fluorescence binding constant data, it is found that L form strong complexes with F^- and HSO₄^- ions through H-bonding interactions. The selective response of F^- over other halides and HSO₄^- amongst other oxo-anions towards L may be explained on the basis of photo-induced electron transfer process.

2 illus, 1 table, 39 ref

042071   PAL A, SONI S (Chemistry Dep, Kurukshetra Univ, Kurukshetra - 136 119,Haryana, Email: palchem21@gmail.com) : Volumetric and acoustic studies of glycine in aqueous solutions of sulphathiazole drug at T=(288.15 to 308.15) K. Indian J Chem Sec A 2020, 59A(12), 1800-8.

The densities (ρ) and speeds of sound (u) for glycine in aqueous solutions of (0.01, 0.02, 0.03, and 0.04) mol·kg^-1 sulphathiazole drug have been measured at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K, using vibrating tube digital densimeter and sound analyser Anton–Paar Model DSA - 5000. The apparent molar properties like apparent molar volume (V_φ), apparent molar adiabatic compressibility (K_φ, _s⁰) and the apparent molar volume (V_φ⁰) and adiabatic compressibility at infinite dilution (K_φ,_s ⁰) of glycine have been determined in water as well as in ternary mixtures containing sulphathiazole drug at different concentrations and at different temperatures from experimental data of densities and speeds of sound under atmospheric pressure. These data were also used to calculate the transfer parameters. Transfer parameters have been explained from the point of view of concentration dependence of solute-solute and solute-solvent interactions. The limiting apparent molar expansibility (E_φ⁰) values for glycine in aqueous solutions of drug have been calculated. The calculated values of thermal expansion coefficient (α₂) have small and positive values. These results are explained on the basis of drug-amino acid - water interactions and hydrophobic –hydrophilic interactions.

4 illus, 7 tables, 45 ref

042070   BALA S, PARTAP R, YADAV O P (Chemistry Dep, Government Coll, Hisar - 125 004, Haryana, Email: rampartap@rediffmail.com) : Effects of Na₂SO₄ and Na₃PO₄ on the surface and thermodynamic properties of an anionic surfactant: bis-(2- ethyl hexyl) sodium sulfosuccinate (AOT) in aqueous solutions. Indian J Chem Sec A 2020, 59A(12), 1793-9.

From tensiometric measurements, critical micelle concentration (CMC), maximum surface excess concentration, minimum area per molecule at the air-liquid interface and thermodynamic parameters of micellization have been determined for an anionic surfactant: bis-(2-ethylhexyl) sodium sulfosuccinate (AOT) in aqueous medium. Effects on the above physico-chemical properties due to added electrolytes: Na₂SO₄ and Na₃PO₄ over a wide range of the surfactant concentrations and at 288.15, 293.15 and 298.15 K have been described in the light of intermolecular interactions. The CMC of AOT is lowered and the micellar stability is improved upon mixing the above electrolytes in aqueous surfactant solution and the same become more pronounced when divalent SO₄^2- are replaced by trivalent PO₄^3-. These observations may be beneficial for improving efficiency of AOT as a detergent, managing oil spill problem, in froth-flotation process for concentrating ores and for efficient recovery of petroleum in the tertiary process.

8 illus, 2 tables, 37 ref

042069   SRINIVASAN B R, DHURI S N, NARVEKAR K U (Goa Univ, Goa - 403 206, Email: srini@unigoa.ac.in) : Crystal structure of potassium hydrogen phthalate revisited. Indian J Chem Sec A 2020, 59A(12), 1785-92.

The present study provides new insight into the structure of potassium hydrogen phthalate 1. The single crystal X-ray structure of 1 consists of a crystallographically independent potassium cation and a unique hydrogen phthalate anion. The µ₄-heptadentate binding mode of the unique hydrogen phthalate ligand organizes the K⁺ ions into a layer resulting in a two-dimensional (2D) coordination polymer. As a result parallel chains of face-sharing {KO₇} polyhedra extending along c are formed. The parallel chains are flanked on either side by hydrogen phthalate wings and are interlinked by vertex sharing of three polyhedra to extend the connectivity along a axis. The structure of 1 is stabilised by π∙∙∙π stacking interactions. A comparative study of the structures of alkali metal hydrogen phthalates is described.

8 illus, 3 tables, 30 ref

042066   MORAJKAR S M, SRINIVASAN B R (Goa Univ, Goa - 403 206, Email: srini@unigoa.ac.in) : Convenient synthesis and Raman spectral characterization of diammonium monomolybdate(VI). Indian J Chem Sec A 2020, 59A(12), 1760-7.

A convenient and cost-effective method is reported for the preparation of gram quantities of an ammonium-rich Mo compound viz. diammonium monomolybdate(VI) (NH₄)₂MoO₄ (1). The process involves a thorough grinding of a commercial sample of ammonium heptamolybdate tetrahydrate (NH₄)₆[Mo₇O₂₄]·4H₂O with an excess of ammonium bicarbonate followed by thermal treatment. The facile formation of (1) is confirmed by its characteristic Raman spectrum. The use of Raman spectroscopy to distinguish between tetrahedral monomolybdate(VI) and heptamolybdate, dichromate and monochromate(VI), paratungstate and monotungstate(VI) as well as the identification of the species present in ammoniacal solutions of MO₃ (M = Cr, Mo, W) are reported.

6 illus, 2 tables, 31 ref

042065   THAKRAL P, SHARMA M, DEWAN D, SHARMA S (Chemistry Dep, St. Stephen’s Coll, Delhi - 110 007, Email: thakralp16@gmail.com) : Analysis of accuracy of burette in determination of surface tension of liquids and study of its variation with detachment time and inclination angle. Indian J Chem Sec A 2020, 59A(11), 1676-84.

A simple laboratory experiment to measure the surface tension of liquids has been proposed in this work, which is well suited for any undergraduate laboratory demonstration. Burette with modified Tate’s law has been found to return surface tension values as good as those obtained using Traube’s stalagmometer. Experimental data and error analysis show similar result accuracy. Also, a comparative study brings to notice the exactitude of drop weight method over drop number method, both from stalagmometer and burette. The rate of flow of 11–23 drops per minute has been found to be highly suitable for minimization of errors due to evaporation and satellite drop formation. Angular dependence of surface tension has been proposed numerically and validated for the respective case with the angle of 0° to deviate the least from literature value. The results obtained in this study are synchronous with the established theoretical understanding of the concept.

7 illus, 8 tables, 19 ref

042063   PATHAK R N, SINGH N, DEVI R (Chemistry Dep, Lucknow Univ, Lucknow - 226 007, Email: mr.nsbaath@gmail.com) : Determination of densities, apparent molar volume and apparent molar volume of transfer of some R₄NI salt solutions in NMF-DMSO mixtures using magnetic float densitometer and then to study of ionic Interaction at 303.15 K. Indian J Chem Sec A 2020, 59A(11), 1660-5.

Binary solvent mixtures of different (%) compositions have been prepared at 303.15 K using tetra alkyl ammonium iodides (R₄NI) of 0.02 M to 0.14 M to investigate inter ionic interaction, ion-ion and ion solvent interactions in NMF-DMSO solvent mixture containing large cations of tetra alkyl ammonium iodides (R₄NI). The densities (ρ₀) of binary solvent mixtures and salt solutions have been measured by magnetic float densitometer. The apparent molar volume at infinite dilution ф_v⁰, in the solvent mixtures, have been utilized to estimate the apparent molar volumes of transfer ∆ф_v⁰ (tr), for various tetra alkyl ammonium iodide salts (R₄NI) from NMF-DMSO mixtures. The observed trend and variations of dielectric constant and density with different (%) composition of NMF – DMSO provide useful information about the structural interactions.

3 illus, 6 tables, 35 ref

042062   SHARMA S K POONAM ( Chemistry Dep, Himachal Pradesh Univ, Shimla - 171 005, Himachal Pradesh, Email: drsklomesh@rediffmail.com) : Molecular interactions studies of doxycycline hyclate in water, aqueous L-phenylalanine and glycyl glycine at different temperatures by using volumetric, ultrasonic and viscometric parameters. Indian J Chem Sec A 2020, 59A(11), 1643-59.

The density, sound velocity and viscosity of doxycycline hyclate in water, aqueous solution of L-phenylalanine and aqueous solution of glycyl glycine have been determined at different temperatures (305.15, 310.15, 315.15 and 320.15) K. The calculated values of partial molar volume (V_ϕ^o), standard partial molar volume of transfer (Δ_tr,V_ϕ^o), partial molar adiabatic compressibility (κϕ^o,_s) and partial molar adiabatic compressibility of transfer (Δ_tr, κϕ^o,_s) for doxycycline hyclate in water, aqueous solution of L-phenylalanine and aqueous solution of glycyl glycine infer the dominance of ion-hydrophilic interactions over hydrophobic-hydrophobic interactions. The Jones-Dole viscosity B-coefficient, viscosity B-coefficient of transfer (ΔtrB), free energy of activation of viscous flow per mole of pure solvent (Δμ₁^o∗) and solute (Δμ₁^o∗) respectively, activation entropy (Δs₂^o*) and activation enthalpy (ΔH₂^o*) of doxycycline hyclate in water, aqueous solution of L-phenylalanine and aqueous solution of glycyl glycine also have been calculated using viscosity data. The structure making and breaking behaviour of doxycycline hyclate in water, aqueous solution of L-phenylalanine and aqueous solution of glycyl glycine are obtained from the values of Hepler’s constant i.e. (δ²V_ϕ^o/δT²) and (dB/dT). The presence and absence of caging effect has been studied with the help of partial molar adiabatic expansibility (E_ϕ^o). The isobaric thermal expansion coefficient (α^o = E_ϕ^o/V_ϕ^o), intermolecular free length and acoustic impedance for doxycycline hyclate in water, aqueous solution of L-phenylalanine and aqueous solution of glycyl glycine also have been determined.

9 illus, 7 tables, 69 ref

042061   TIAN F, LI S-Y (Chemistry Dep, Taiyuan Normal Univ, Shanxi 030619, China, Email: lisy56@163.com) : Study of spectrophotometric characteristics of the charge transfer complexation of epsilon aminocaproic acid with bromanil. Indian J Chem Sec A 2020, 59A(11), 1637-42.

A spectrophotometric method has been studied for the determination of epsilon aminocaproic acid (EACA) through charge transfer (CT) complexation with bromanil (TBBQ). The CT reaction has been carried out at 70 °C of the water bath for 30 min in the borax buffer solution. The spectrum obtained for EACA/TBBQ system shows the maximum absorption band at wavelength of 352 nm. The CT complex is also confirmed by both FTIR and ¹H NMR measurements. The stoichiometry of the CT complex is found to be 1:1 ratio by Job and straight line methods between the donor and the acceptor. At the optimum reaction conditions, Beer’s law is obeyed in a concentration limit of 2～8 µg mL⁻¹. The relative standard deviation is less than 1.5 %. The apparent molar absorptivity is determined to be 1.16×10⁴ L mol⁻¹ cm⁻¹ at 352 nm. The thermodynamic properties and reaction mechanism of the CT complexation have been discussed. The developed method could be applied successfully for the determination of the studied compound in its pharmaceutical dosage form with a good precision and accuracy compared to official method as revealed by t- and F-tests.

5 illus, 4 tables, 25 ref

042057   TUNC T, ERTABAKLAR H, KARACAN N (Chemistry and Process Engineering Dep, K?rsehir Ahi Evran Univ, K?rsehir, 40100, Turkey, Email: ttunc@ahievran.edu.tr) : In vitro anti-leishmanial activities and structure-activity relationship analysis of new antimony(III) complexes. Indian J Chem Sec A 2020, 59A(11), 1609-17.

New fourteen antimony(III) complexes of general formula [SbL_nCl₃] (where n= 1 or 2, L =2-aminopyridine, 5-methyl-2-aminopyridine, 2-aminopyrimidine, 4,6-dimethoxy-2-aminopyrimidine, 2-benzyl-2-thiopseudeourea,2-guanidinobenzimidazole, 2-amino-5-thiol-4,6-dimethoxypyrimidine, 2-amino-5-(1H-tetrazol-5-ylthio)-4,6-dimethoxypyrimidine, N-2-pyrimidine, 2-piperidinecarboxamide, N-2-pyrimidine, 2-pyrrolidinecarboxamide, 2-amino-5-(1H-tetrazol-5-iltiyo)-4,6-dimethoxypyrimidine-2-pyrrolidinecarboxamide and N-2-pyrimidine, 5-chloro-2-thiophenecarboxamide, N-2-benzothiazol-2-pyrrolidinecarboxaamide, N,N-(1,2-phenyl)dipyrrolidine-2-carboxamide) have been synthesized and their anti-leishmanial activity have been assessed in vitro against Leishmania tropica promastigotes. The best complex, Sb(2-guanidinobenzimidazole)Cl₃ is demostrated 3.16 % growth inhibition at a concentration of 31.25 μg/mL. In general, antimony(III) complexes containing pyrimidine ligands has showed higher anti-leishmanial activity than antimony(III) complexes bearing pyridine ligands, and electron-donating substituents decrease the anti-leishmanial activity. All complexes have been optimised with DFT/B3LYP/LANL2DZ method in the gas phase. Several descriptors are tested to find a quantitative correlation between anti-leishmanial activity and structural properties of the complexes by best multiple linear regression method. Good correlations are obtained with minimum net atomic charge for a C atom and maximum bond order of a Cl atom. The developed QSAR equation is internally validated.

4 illus, 4 tables, 43 ref

042056   KAUSHIK R, HUSSAIN F (Chemistry Dep, Delhi Univ, Delhi - 110 007, Email: fhussain@chemistry.du.ac.in) : Synthesis and characterization of nanoclusters: Inorganic-organic hybrid copper and cobalt containing arsenotungstates(III) with lone pair on heteroatom incorporating bidentate N-donating ligands. Indian J Chem Sec A 2020, 59A(11), 1602-8.

Three inorganic-organic hybrid nanoclusters of copper and cobalt containing arsenotungstates with lone pair on heteroatom have been synthesized under mild reactions conditions. All the compounds have been characterized by single crystal X-ray diffraction, Fourier transform infrared, UV/visible spectroscopy, thermogravimetric and field emission scanning electron microscopic (FE-SEM) analysis. The compound [NaRb{Cu(phen) (H₂O)₂Cl}₂][{Cu(phen)(H₂O)}₂{Cu(phen)(H₂O)Cl}₂{Cu₂As₂W₁₉O₆₇(H₂O)] (1a) is a sandwiched type arsenotungstate with two copper atoms in square planar environment in the belt region. The polyanion-1 is decorated by four copper phenanthroline complexes through a terminal oxygen atom of the polyanion. In addition, two other cobalt containing inorganic-organic hybrid lone pair containing arsenotungstates(III) with 1,10-phenanthroline [NaRbCo(phen)₃][{Co(phen)(H₂O)₃}CoAs₂W₂₀O₆₇(H₂O)₃] (2a) and 2,2’-bipyridine[Na₃RbCo(2,2-bipy)₃][CoAs₂W₂₀O₆₇(H₂O)₃] (3a) has also been synthesized under mild conditions. The polyanion (2) is a mono cobalt substituted sandwiched type structure that is decorated by a cobalt phenanthroline complex attached to the polyanion through a terminal oxygen atom. Meanwhile the other complex (3) is also a monocobalt substituted sandwiched type structure which contains a cobalt 2,2’-bipyridine complex in the cationic part. Polyanion-1 shows intermolecular π-π stacking interaction between the phenanthroline ligand in the cationic part and one that is attached directly to the polyanion. The compounds are also characterized by FE-SEM analysis and the compound 3a shows ultra- smooth cuboids with grain size in the range of 1 to several micrometer though some very small irregular particles with the size of a few micrometer were also observed.

4 illus, 1 table, 28 ref

042055   PAL D (Chemistry Dep, Sreegopal Banerjee Coll, Magra, Hooghly, West Bengal, Email: debu_magra@yahoo.co.in) : Synthesis of metal oxide nanoparticles - A general overview. Indian J Chem Sec A 2020, 59A(10), 1513-28.

Metal oxide nanoparticles (MONPs) are the most important class of nanoparticles regarding the volume of production and application potential in diversified fields. The research domain of MONPs is vastly expanding and rationally million of bytes are utilized to cover the literature each day around the globe. They can be synthesized in a variety of processes and the MONPs produced through different processes differ greatly regarding morphology, texture and functionality. Therefore fine tuning of process control in synthetic methodology is under extensive research along with relevant structures and properties so as to fit the need. Improvisations in synthetic procedures are always attempted and newer dimensions of applicability are being explored. The MONPs find extensive use in the field of optoelectronics, gas sensing, surface coating, biomedicine, fuel cells, catalysis and in so many fields. This review attempts solely to cover a general outline of the synthetic methods of production of MONPs and metal oxide nanostructures.

1 illus, 170 ref

042052   RAGHUVANSHI U, SAPRE N S (Applied Chemistry Dep, SGSITS, Indore, Madhya Pradesh - 452 003, Email: sukusap@yahoo.com) : In silico de novo design of NNRTIs of HIV-1: Functional group based computational molecular modelling approach. Indian J Chem Sec A 2020, 59A(10), 1484-93.

Seven novel lead compounds, acting as NNRTIs of HIV-1, are extracted from a database of, in silico de novo designed, 500 compounds. Functional group based computational molecular modelling techniques are used for such design of Acylthiocarbamate derivatives. Effect of structural characteristics on the antiviral activity of these derivatives has also been studied. Statistical regression techniques namely, Non-linear (Back Propagation Neural Network, Support Vector Machine) and linear (Multiple Linear) chemometric regression methods are used in developing the relationships of Kier-Hall Electrotopological State Indices (E_RingA, E_O8, E_N9, E_O14, E_S16, E_N17, E_O19, E_{R, and} E_R1) with the HIV-1 antiviral activity. The relative potentials of these methods are also assessed and the results suggest that BPNN (r² = 0.845, MSE = 0.142, q² = 0.818) describes the relationship between the descriptors and antiviral activity in a relatively better manner than SVM-ε-radial (r² = 0.844, MSE = 0.144, q² = 0.807) and MLR (r² = 0.836, MSE = 0.150, q² = 0.805).

4 illus, 4 tables, 50 ref

042051   GOGOI P, BORUAH K, BORAH R (Chemical Sciences Dep, Tezpur Univ, Napaam - 784 028, Assam, Email: ruli@tezu.ernet.in) : Studies on coordination environment of transition metal chloride anionic speciation of N, N-disulfodiisopropylammonium ionic salts and assessment of their Bronsted-Lewis acidic properties. Indian J Chem Sec A 2020, 59A(10), 1476-83.

Four ionic salts of N, N-disulfodiisopropylammonium cation with complex anionic speciation of metal chlorides such as [FeCl₄]^-, [NiCl₄]^2-, [Zn₂Cl₆]^2-/[Zn₄Cl₁₀]^2-, [CoCl₄]^2-/[CoCl₃]^- have been synthesized and characterized with FTIR, NMR, TGA, Raman and electronic spectra. Comparative Brønsted and Lewis acidic strength of the salts have been assessed for catalytic uses in organic reactions via UV-visible Hammett plot and FTIR spectra using pyridine as probe molecule. Band gap values obtained from Tauc plot present their semiconductor behavior to design ionic liquid-based photo catalysts in future.

7 illus, 1 table, 27 ref

042050   BASAVARAJ T, CHIMATADAR S A, NANDIBEWOOR S T (Chemistry Dep, Karnatak Univ, Dharwad - 580 003, Email: stnandibewoor@yahoo.com) : A kinetic and mechanistic study of oxidation of L-lysine by diperiodatonickelate(IV) in aqueous alkaline medium. Indian J Chem Sec A 2020, 59A(10), 1470-5.

The kinetics of oxidation of L-lysine by diperiodatonickelate(IV) (DPN) in aqueous alkaline medium at a constant ionic strength of 0.60 mol dm^-3 has been studied spectrophotometrically. The reaction shows first order in diperiodatonickelate(IV) and less than unit order dependence each in lysine and OH^- ion concentrations. The addition of periodate retards the reaction, while the product nickel(II) do not show any significant effect on the reaction rate. An increase in ionic strength and decrease in dielectric constant of the medium decreases the rate. A mechanism based on experimental results is proposed. The constants involved in the mechanism are evaluated. The activation parameters with respect to slow step of the mechanism are computed and discussed.

3 illus, 2 tables, 14 ref

042049   DROLIYA P, CHAND D, NAIN A K (Chemistry Dep, Dyal Singh Coll, New Delhi - 110 003, Email: ak_nain@yahoo.co.in) : Experimental and theoretical studies of transport and optical properties of binary mixtures of acetonitrile with some alkyl methacrylates at temperatures from 298.15 to 318.15 K. Indian J Chem Sec A 2020, 59A(10), 1457-69.

The viscosities, η and refractive indices, n_D of pure acetonitrile, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate and of their binary mixtures with acetonitrile as the common component, covering the entire composition range has been measured at temperatures (298.15, 303.15, 308.15, 313.15 and 318.15) K and atmospheric pressure. Using these experimental data, the deviations in viscosity ∆η, deviations in refractive index, ∆n_D, deviations in molar refraction, ∆R_Mhave been calculated. These excess properties are correlated by the Redlich-Kister polynomial equation. The variations of ∆η, ∆n_D, ∆R_M and with composition and temperature has been discussed in terms of intermolecular interactions existing in these mixtures. Further, the viscosities and refractive indices of these binary mixtures have been calculated theoretically by using various empirical and semi-empirical relations and the results are compared with the experimental findings.

5 illus, 6 tables, 54 ref

042048   RAMA I, SUBASHINI A, SELVAMEENA R (Chemistry Dep, Affiliated to Bharathidasan Univ, Tiruchirappalli - 620 002, Tamil Nadu, Email: rama14jai@yahoo.co.in) : Crystal structure, Hirshfeld surface analysis, DFT and TD-DFT studies of nickel(II) monohydrate complex coordinated by bis (5-bromo-1-formylphenolate) moiety and two water molecules. Indian J Chem Sec A 2020, 59A(10), 1449-56.

In the title compound [Ni(C₇H₅O₂Br)₂(H₂O)₂]H₂O, the Ni atom adopts distorted octahedral geometry in which the bidentate ligand acts as O,O’ donor defining an equatorial plane and water molecules occupy the axial positions. It is a mononuclear compound. This compound is crystallized on the monoclinic system, space group P2₁/c with the unit cell parameters a = 18.4561(8) Å, b = 7.3442(4) Å, c = 14.5786(8)Å, α= 90°, β= 109.057°, γ = 90° and Z = 4. The two hydroxyl groups are deprotonated and oxygen anions get coordinated with nickel. The supramolecularself-assembly of the complex is also stabilized by weak non-covalent interactions in the crystal packing, which is further quantified by using Hirshfeld surface analysis. The molecular architecture of the complex is examined by quantum chemical calculations using DFT and is compared with crystalline structure of the same. The electronic excitation energies of the complex have been simulated at TD-DFT level and are evaluated with experimental electronic spectrum.

10 illus, 5 tables, 24 ref

042047   YAN H, WANG Q, HE Y, SHEN Y, SONG P, WANG R (Northwest Normal Univ, Lanzhou 730070, China, Email: heyufeng@nwnu.edu.cn) : Loess particles loaded petaloid Bi₂S₃ nanowires for highly efficient photodegradation of dyesunder sunlight. Indian J Chem Sec A 2020, 59A(10), 1442-8.

In this paper, using loess particles (LoP), a kind of extremely common and inexpensive natural silicate particles with metastable structure, as inorganic carrier, the petaloid Bi₂S₃nanowires have been loaded by in-situ depositing, which afforded loess particles loaded petaloid Bi₂S₃nanowires (PBiNw@LoP) with one-step hydrothermal procedure. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and adsorption-desorption isotherms of N₂ have been employed to characterize the prepared composite photocatalyst. The results show that the petaloid Bi₂S₃nanowires are evenly dispersed on the loose surface of loess particles. The photocatalytic activity of PBiNw@LoP is evaluated by photodegradation of methylene blue (MB) irradiated with sunlight. It is demonstrated that PBiNw@LoP exhibits the superior photocatalytic performance with the photocatalytic degradation rate of 99.5 %. The petaloid Bi₂S₃ nanowires with larger specific surface helps to absorb light, while the loose surface of loess with certain adsorption capacity. Therefore, the photocatalytic activity has been improved by the synergistic effect in photodegradation of dyes, while the ratio of Bi₂S₃ in catalyst is decreased without affecting the photodegradation performance. In conclusion, a cheap and efficient photocatalyst has been successfully prepared for the degradation of dye wastewater.

10 illus, 1 table, 35 ref

042045   BHAVYA P V, PUNITHAVATHI P,DAS T M (Chemistry Dep, Central Univ of Tamil Nadu (CUTN), Thiruvarur - 610 005, Tamil Nadu, Email: tmohandas@cutn.ac.in) : Design, synthesis and characterisation of a disulphide appended sugar bis-triazole. Indian J Chem Sec A 2020, 59A(09), 1364-8.

In this work, sugar-based bis-triazole appended disulfide was synthesized, characterized and the molecular structure is confirmed through different spectral techniques like NMR (¹H, ¹³C), FTIR and mass spectroscopy. Since the target molecule possesses suitable core moiety, we anticipate that the synthesized sugar-based bis-triazole appended disulfide derivative can act as a sensor.

1 illus, 25 ref