Synthetic Aziridines in Medicinal Chemistry: A Mini-Review.

Azaheterocyclic compounds are well-known to have diverse types of biological activity. Among them, azacyclopropanes, commonly referred as aziridines, occupy a prominent place in synthetic organic and medicinal chemistry due to its occurrence in natural resources, complexity involved in synthesis due to ring-strain, building blocks in organic synthesis, and its biological properties. Several novel compounds containing aziridine ring have been designed and synthesized recently by medicinal chemists for evaluating their biological profile.

Antimicrobial, crown gall tumor inhibitory and cytotoxicity assays of N-[(1-methyl-1H-indole-3-yl)methylene]amines synthesized by an improved protocol.

The present paper reports an easy preparation of imines of N-methyl-1H-indole-3-carboxaldehyde by its condensation with alkyl and aromatic amines in ethanol without using any catalyst or dehydrating agent. The compounds have been screened for their antibacterial, antifungal, crown gall tumor inhibitory, and cytotoxic activities. As a major finding some of the compounds exhibited potential biological activity.

Evaluation of some classical hydrazones of ketones and 1,2-diketones as antileishmanial, antibacterial and antifungal agents.

The paper describes the synthesis and antimicrobial (antileishmanial, antibacterial and antifungal) activity of some classical hydrazones of benzophenones and of 1,2-diketones. N-(Diaryl) acyl derivatives of these hydrazones have also been synthesized and evaluated. 4,4,-Demthoxybenzil monohydrazone and 4,4'-dimethoxybenzophenone hydrazone showed significant antileishmanial activity.

Synthesis of N-(1-methyl-1H-indol-3-yl)methyleneamines and 3,3-diaryl-4-(1-methyl-1H-indol-3-yl)azetidin-2-ones as potential antileishmanial agents.

A series of N-(1-methyl-1H-indol-3-yl)methyleneamines and eight new 3,3-diaryl-4-(1-methyl-1H-indol-3-yl)azetidin-2-ones have been synthesized and screened for their antileishmanial activity against Leishmania major. 3,3-Diaryl-4-(1-methyl-1H-indol-3-yl)azetidin-2-ones have been synthesized by the Staudinger's ketene-imine cycloaddition employing two 2-diazo-1,2-diarylethanones as the precursors of diarylketenes. A marked improvement in anti-parasitic activity is observed by transformation of the methyleneamines to azetidin-2-ones in seven out of eight compounds.

Recent progress in synthesis and bioactivity studies of indolizines.

The present review describes the recent progress in synthetic approaches to construct indolizine framework (including partially or wholly reduced ring) and the design of such compounds with potential biological activity. The methods of synthesis are classified as the Tschitschibabin reaction, 1,3-dipolar cycloadditions, cyclisation reactions depending on the position of bond formation, and other methods. The biological activities include antimicrobial activity, antioxidant activity, anti-inflammatory activity, anticonvulsant activity, enzymes inhibition activity and activity as calcium entry blocker.

Synthesis and antimicrobial activity of new 1-alkyl/cyclohexyl-3,3-diaryl-1'-methylspiro[azetidine-2,3'-indoline]-2',4-diones.

The paper describes the synthesis of new 1-alkyl/cyclohexyl-3,3-diaryl-1'-methylspiro[azetidine-2,3'-indoline]-2',4-diones from the reactions of the 2-diazo-1,2-diarylethanones with 1-methyl-3-(alkyl/cyclohexylimino)indolin-2-ones under thermal condition. The compounds, characterized by satisfactory analytical and spectral (IR, (1)H NMR and (13)C NMR) data, have been screened for their antibacterial and antifungal activities.

Spectroscopic characterization of the 1-substituted 3,3-diphenyl-4-(2'-hydroxyphenyl)azetidin-2-ones: application of (13)C NMR, (1)H-(13)C COSY NMR and mass spectroscopy.

The article deals with spectroscopic characterization of azetidin-2-ones. The presence of substituents like hydroxyl, fluoro, methoxy and benzhydryl, etc., on the azetidin-2-one ring significantly affects the IR absorption and (13)C NMR frequencies of the carbonyl group present in these compounds.

Synthesis of 2-azetidinones from 2-diazo-1, 2-diarylethanones and N-(2-thienylidene)imines as possible antimicrobial agents.

An equimolar reaction of 2-diazo-1, 2-diarylethanones with N-(2-thienylidene)imines affords 1-substituted-3, 3-diaryl-4-(2-thienyl)-2-azetidinones in excellent yields. The products have been characterized on the basis of satisfactory analytical and spectral (IR, 1H and 13C NMR, MS) data. The mechanism of formation of the products is shown.