Prakash N. Chavan

Enantioselective syntheses of (R)-pipecolic acid, (2R,3R)-3-hydroxypipecolic acid, β-(+)-conhydrine and (−)-swainsonine using an aziridine derived common chiral synthon

Concise total syntheses of (R)-pipecolic acid, (R)-ethyl-6-oxopipecolate, (2R,3R)-3-hydroxypipecolic acid and formal syntheses of β-(+)-conhydrine, (−)-lentiginosine, (−)-swainsonine and 1,2-di-epi-swainsonine have been accomplished starting from a common chiral synthon. The present strategy employs regioselective aziridine ring opening, Wittig olefination and RCM as the key chemical transformations.

Influence of high ash Indian coals in fluidized bed gasification under different operating conditions

Coal gasification has been internationally accepted as one of the most viable and effective clean coal technology for power generation. Presently, the coal being produced in India is having high ash content and it is a major constraint for most of the commercial applications in process industries. The present paper deals with the variation of higher heating value (HHV) of the product gas and carbon conversion with different inherent properties under different operating conditions in fluidized bed gasification. It has been observed that HHV of product gas increases with volatile mater, fixed carbon and temperature, whereas, mineral matter, air and steam show decreasing effect on HHV. On the other hand, carbon conversion increases with volatile matter, air, steam and temperature. It has also been observed that mineral matter provides catalytic effect to a certain level for carbon conversion, whilst, decreasing trend has been observed with the fixed carbon.

A concise synthetic approach toward tamiflu (oseltamivir phosphate): cis-aziridine as the key synthon and RCM

The key synthon cis-aziridine has been efficiently utilised for the synthesis of oseltamivir phosphate, using Wittig olefination, Barbier addition, Mitsunobu reaction and ring closing metathesis (RCM) as key essentials.

Stereospecific synthetic approach towards Tamiflu using the Ramberg–Backlund reaction from cysteine hydrochloride

The stereospecific formal synthesis of Tamiflu from L-cysteine hydrochloride as the chiral source is described. The notable feature of the present strategy is the Ramberg–Backlund reaction and Sharpless–Reich protocol as the key chemical transformations to access the cyclohexene skeleton of Tamiflu.