Braj Bhushan Lohray

Novel phthalazinone and benzoxazinone containing thiazolidinediones as antidiabetic and hypolipidemic agents

We report here the synthesis of a series of 5-[4-[2-[substituted phthalazinones-2(or 4)yl]ethoxy]phenylmethyl]thiazolidine-2,4-diones and 5-[4-[2-[2,3-benzoxazine-4-one-2-yl]ethoxy]phenylmethyl]thiazolidine-2,4-diones and their plasma glucose and plasma triglyceride lowering activity in db/db mice. In vitro PPARgamma transactivation assay was performed in HEK 293T cells. In vitro and in vivo pharmacological studies showed that the phthalazinone analogue has better activity. PHT46 (compound 5a), the best compound in this series, showed better in vitro PPARgamma transactivation potential than troglitazone and pioglitazone. In insulin resistant db/db mice, PHT46 showed better plasma glucose and triglyceride lowering activity than the standard drugs. Pharmacokinetic study in Wistar rats showed good systemic exposure of PHT46. Subchronic toxicity study in Wistar rats did not show any treatment-related adverse effect.

Synthesis and biological activity of novel pyrimidinone containing thiazolidinedione derivatives

A series of pyrimidinone derivatives of thiazolidinediones were synthesized. Their biological activity were evaluated in insulin resistant, hyperglycemic and obese db/db mice. In vitro PPARgamma transactivation assay was performed in HEK 293T cells. PMT13 showed the best biological activity in this series. PMT13 (5-[4-[2-[2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl]ethoxy]phenylmethyl]thiazolidine-2,4-dione) showed better plasma glucose, triglyceride and insulin-lowering activity in db/db mice than rosiglitazone and pioglitazone. PMT13 showed better PPARgamma transactivation than the standard compounds. Pharmacokinetic study in Wistar rats showed good systemic exposure of PMT13. Twenty-eight day oral toxicity study in Wistar rats did not show any treatment-related adverse effects.

Novel pyrrole-containing hypoglycemic and hypotriglyceridemic compounds*

Several substituted α-alkoxy phenyl propionic acids were synthesized, and their hypotriglyceridemic properties were evaluated in Swiss albino mice. Some of the compounds showed excellent triglyceride- and cholesterol-lowering properties even at a dose of 1 mg/kg. 2,5-Substituted pyrrole-containing heterocycles were among the most potent alkoxy propionic acid class of compounds. These compounds also showed excellent antidiabetic activities in animal models.

A Practical Approach to the Synthesis of Dianhydro Sugars

Abstract Chiral tetrols derived from various carbohydrate precursors have been converted into the corresponding dianhydro sugar derivatives in a one pot procedure. The course of reaction very much depends upon the protecting groups used. In case of D-mannitol and sorbitol, it has been shown that when 3,4-hydroxy groups are protected as trans-acetonide group, the present methodology furnished exclusively 1,2: 5,6-dianhydro derivatives in excellent yield. However, if the 3,4-hydroxy groups are protected with benzyl group a mixture of products consisting of dianhydro sugar, a furan and a bicyclo[2.2.2]octane derivatives were obtained. This method has also been used to synthesize dianhydro sugars in which the two diol moieties are placed adjacent to each other or separated by one or more carbon atoms.

Novel anti-infective compounds

A set of substituted piperazinyloxazolidinone derivatives has been studied for their antibacterial activity in a few gram-positive bacteria. The structural modifications have provided a superior compound than linezolid, the only drug of this class in the market at present.