Concept-Driven Chemoselective O/N-Derivatization of Prolinol: A Bee-Line Approach to Access Organocatalysts.

An investigation into the sensitivity of reaction conditions to a highly utilized protocol has been reported, wherein the mono-Boc functionalization of prolinol could be controlled for the exclusive synthesis of either -Boc, -Boc, or oxazolidinone derivatives. Mechanistic investigation revealed that the elementary steps could possibly be controlled by (a) a requisite base to recognize the differently acidic sites (NH and OH) for the formation of the conjugate base, which reacts with the electrophile, and (b) the difference in nucleophilicity of the conjugate basic sites. Herein, a successful chemoselective functionalization of the nucleophilic sites of prolinol by employing a suitable base is reported.

Spectroscopic and Computational Study of the Organocatalytic Umpolung of Bromocations: An Accelerated Stereoselective Dibromination Protocol.

Herein, organocatalytically achieved polarity reversal of cationic bromine is presented. The proven bromocation source N-bromosuccinimide (NBS) was converted to a superior bromoanion reagent by H/Br exchange with a secondary amine, substantiated with spectroscopic and computational evidence. The concept has further been used in a successfully accelerated organocatalyzed dibromination of olefins in a non-hazardous, commercially viable process with a wide range of substrate scope.

Characterization of exopolysaccharide derived from and its possible role as an emulsifier.

Unlabelled: is an oral growing bacteria responsible for teeth blackening. It can form biofilm. The exopolysaccharide (EPS) cluster associated with biofilm formation was isolated using ethanol precipitation and the formaldehyde-sodium hydroxide method.