Sonika Jain

Use of 2,4,6-trichloro-1,3,5-triazine (TCT) as organic catalyst in organic synthesis

ABSTRACT Organic catalysts have found wide applications in organic synthesis. Many organic reactions, which originally do not occur under normal conditions or are difficult to operate normally, have been successfully conducted under mild conditions in the presence of catalysts. In recent years, 2,4,6-trichloro-1,3,5-triazine (TCT, cyanuric chloride) has been used as organic catalyst in many organic synthesis, because it is stable, nonvolatile, inexpensive, commercially available, and easy to handle. On account of these properties it has been used as a green catalyst and sometimes is a catalyst of choice in organic reactions. GRAPHICAL ABSTRACT

Synthesis and Antimicrobial Evaluation of Some Novel Trisubstituted s-Triazine Derivatives Based on Isatinimino, Sulphonamido, and Azacarbazole

A study directed towards exploring the temperature-dependent reactivity of the chlorine atoms of 2,4,6-trichloro-s-triazine (TCT) in the nucleophilic displacement reaction, allowed a facile replacement of its chlorine atoms in succession with (i) N-amino methyl substituted isatin-3-hydrazones, (ii) N1-substituted-4-amino benzene sulphonamides, and (iii) 8-amino-4-oxo-N-benzyl-azacarbazole to produce the corresponding 2,4,6-trisubstituted-s-triazine, namely; 2-(N-amino methyl substituted isatin-3-hydrazinyl)-4-(N1-substituted-4′-amino benzenesulfonamidyl)-6-(8′-amino-4′-oxo-N-benzylazacarbazolyl)-1,3,5-triazine derivatives in acceptable yields. The compounds prepared were further evaluated for their antibacterial activity against E. coli and B. subtilis and antifungal activities against A. niger and A. flavus, and some of them showed promising activity profile.

Gastroprotective activity of reconstituted red fruit pulp concentrate of Citrullus lanatus in rats

Aim: This study was carried out to evaluate the gastroprotective potential of the aqueous fruit pulp concentrate of Citrullus lanatus citroides (CLC) on pyloric ligation and indomethacin-induced ulcer in Wistar albino rats. Materials and methods: In indomethacin-induced ulcer model, CLC was administered in the doses of 250 mg/kg, 500 mg/kg and 1000 mg/kg body weight orally, tds for 5 days. The antiulcer activity was determined via observing reduction in ulcer index whereas in the pyloric ligation model, the gastroprotective effect of CLC was assessed from the alteration in volume of gastric juice, pH, free and total acidity, protein concentration in gastric juice. Further lipid peroxide (LPO), and activities of enzymic antioxidants such as superoxide dismutase (SOD) and catalase (CAT) was also determined along with the levels of hexose, hexosamine, sialic acid, fucose in gastric mucosa. Results: In both models, treatment with CLC caused a significant reduction in lesion index when compared to vehicle treated group, providing evidence for antiulcer capacity. In pyloric ligation model, pretreatment with CLC resulted in significant increase in pH, enzymic antioxidants, that is, SOD, CAT, with a significant decrease in volume of gastric juice, free and total acidity, protein concentration, acid output, and LPO levels respectively. The presence of the flavonoids and polyphenols may be responsible for the gastroprotective effect of CLC. Conclusions: The aqueous fruit pulp concentrate of CLC showed significant gastroprotective potential against pyloric ligation and indomethacin-induced ulceration in rats.

An Efficient Approach to the Synthesis of Novel Oxazolidinones as Potential Antimicrobial Agents

Oxazolidinone, either mononuclear or condensed with other heterocyclics, has established its importance in medicinal chemistry. A variety of biological activities have been reported by oxazolidinone derivatives. The present work describes the synthesis of several oxazolidinone derivatives, 3-(2-(7-chloroquinoline-4-ylamino)ethyl)-2-imino-5-(4-chloro/nitro/methoxy benzylidene)oxazolidin-4-one 4(a–c) and 4-(2-(7-chloroquinolin-4-ylamino)ethyl)-2(4-chloro/nitro/methoxy-benzylidene)-1,6-diox-4,9-di-azaspiro[4,4]nonane-3,8-dione 5(a–c). Synthesized compounds (1, 3, 4a, 5a, and 5c) were screened against bacterial strains such as S. aureus (MTCC 96) and E. coli (MTCC119) and fungal strains A. niger (MTCC 1344) and C. albicans (MTCC 871) compared with penicillin for bacteria and fluconazole for fungi as reference drugs by disk diffusion method. All synthesized compounds were identified by the means of IR, NMR, and MS.

Application of novel precursors derived from carbazolo condensed azepinones to the direct single step synthesis of corresponding isoxazole and pyrazole annulated analogues of medicinal importance

Exceedingly facile protocols based on the reactivity of corresponding oxoketenedithioacetal (4), 2-(dimethylaminomethylene) ketone (5), β-oxoenolether (6) and α, β-unsaturated ketone (7) resulted from 7-ethyl-3,4 dihydroazepino[3,2-b] carbazole-2,5 (1H,7H)-dione (3) on its reaction with base catalyzed condensation of (a) CS2+ MeI (b) DMF-DMA (c) H-COOEt and (IV) C6H5CHO respectively, has been explored to provide an easy access of their isoxazole and pyrazole annulated analogues (8–13) of medicinal interest. The key compound 3 from which, the synthesis proceeded was in turn realized on the reaction of commercial 3-amino-9-ethyl carbazole (1) with ethyl succinyl chloride, under the conditions of Friedel-Crafts acylation followed by cyclocondensation of the resulting intermediate 2 with PPA. Isoxazolo and pyrazolo annulated analogues of carbazolo condensed azepinone derivatives (8–13) were screened for their in-vitro antimicrobial potential against various bacterial and fungal species. Besides this pyrazole derivative (8) was also evaluated for its CNS depressant potential in mice using photoactometer.

The Synthetic and Biological Attributes of Pyrazole Derivatives: A Review

Pyrazole nucleus is a unique structural scaffold which acts as an interesting template for combinatorial as well as medicinal chemistry. This review presents a detailed overview on the synthesis, QSAR and pharmacological applications of pyrazole. In addition, it covers most recent reports on structural modifications on pyrazole illustrating vital structural activity relationship.