Hanumant B. Borate

Microwave assisted solvent-free synthesis of dihydropyrimidinones by Biginelli reaction over Si-MCM-41 supported FeCl3 catalyst

Abstract Among the Si-MCM-41 or montmorillonite K 10 clay supported ZnCl 2 , AlCl 3 , GaCl 3 , InCl 3 and FeCl 3 catalysts, FeCl 3 /Si-MCM-41 shows best performance for the microwave-assisted synthesis of dihydropyrimidinones by the Biginelli reaction involving multicomponent condensation of aromatic aldehyde, ethyl acetoacetate and urea in the absence of any solvent. It is a promising catalyst for the microwave-assisted reaction providing high product yield in a short period (3.0–5.0 min).

Natural kaolinitic clay: A remarkable reusable solid catalyst for the selective functional protection of aldehydes and ketones

Abstract Natural kaolinitic clay possessing transition metals such as Fe and Ti in its lattice has been found to catalyze efficiently the chemoselective acetalization and thioacetalization of variety of carbonyl compounds with ethane-1,2-diol and ethane-1,2-dithiolrespectively.

Fluconazole analogues containing 2H-1,4-benzothiazin-3(4H)-one or 2H-1,4-benzoxazin-3(4H)-one moieties, a novel class of anti-Candida agents

As a part of our program to develop new antifungal agents, a series of fluconazole analogues was designed and synthesized wherein one of the triazole moieties in fluconazole was replaced with 2H-1,4-benzothiazin-3(4H)-one or 2H-1,4-benzoxazin-3(4H)-one moiety. The new chemical entities thus synthesized were screened against various fungi and it was observed that the compounds 4a and 4i are potent inhibitors of Candida strains. The structure-activity relationship for these compounds is discussed.

BENZYLTRIMETHYLAMMONIUM HYDROXIDE CATALYSED NITROALDOL CONDENSATION

Benzyltrimethylammonium hydroxide is found to be a very efficient catalyst for nitroaldol condensation in a short time with excellent yield.

A convenient approach to the total synthesis of (±) 4-demethoxydaunomycinone

A convenient and most practical approach to the synthesis of (±) 4-demethoxydaunomycinone starting from 2-methylhydroquinone is described.

Novel hybrids of fluconazole and furanones: design, synthesis and antifungal activity.

During our efforts to develop new antifungal agents, a number of hybrid molecules containing furanones and fluconazole pharmacophores were designed and synthesized. The new chemical entities thus synthesized were tested for their potential as antifungal agents against various fungal strains and it was observed that the compounds with general structure 7 were potent inhibitors of Candida albicans ATCC 24433, Candida glabrata ATCC 90030, Candida tropicalis ATCC 750 and Candida neoformans ATCC 34664 while the fluconazole analogues 12 exhibited antifungal activity against Candida albicans ATCC 24433 and Candida glabrata ATCC 90030. The structure-activity relationship for these compounds is discussed. The synthetic strategies used in the present work have potential to prepare a large number of compounds for further refinement of structures to obtain molecules suitable for development as antifungal drugs.

Total synthesis of (±)-brasiliquinone B

Abstract The total synthesis of (±)-brasiliquinone B has been achieved via a Friedel–Crafts alkylation approach. In contrast, a Friedel–Crafts acylation approach for the synthesis of (±)-brasiliquinone B resulted in formation of A ring aromatized tetracyclic products.

First total synthesis of (±)-brasiliquinone B

Abstract Brasiliquinone B (2) was synthesized from 7-methoxy-1-tetralone in 8 steps making use of Friedel-Crafts alkylation as a key step.

The preparation of the first α-vinylidenepenams

Abstract Benzyl esters of the first 6-vinylidenepenams have been prepared by reaction of 6-position propargylic triflates with higher order organocuprates. This methodology permits a great deal of versatility in the introduction of substituents at the terminal allenyl position.

Synthesis of Substituted 2,6-Dicyanoanilines and Related Compounds. A Review

Introduction ................................................................................. 468 I. 2,6-Dicyanoaniline ........................................................................ 469 II. Monosubstituted 2,6-Dicyanoanilines ............................................ 470 1. 3 (5)-Substituted 2,6-Dicyanoanilines ....................................................470 2. 4-Substituted 2,6-Dicyanoanilines .........................................................472 III. Disubstituted 2,6-Dicyanoanilines ................................................. 474 1. 3,4 (4,5)-Disubstituted 2,6-Dicyanoanilines............................................474 2. 3,5-Disubstituted 2,6-Dicyanoanilines....................................................478 IV. Trisubstituted 2,6-Dicyanoanilines ................................................ 491 Conclusion.................................................................................... 511 References .................................................................................... 511