Chinmay Bhat

Recent advances in the synthesis of naturally occurring pyrrolidines, pyrrolizidines and indolizidine alkaloids using proline as a unique chiral synthon

The present article describes the synthesis of a wide spectrum of natural products of the class pyrrolidines, pyrrolizidines and indolizidines using proline as a viable synthetic precursor. The review emphasizes the versatility of the basic unit of proline as a useful chiral synthon confined for the synthesis of only natural products of the above mentioned families. The vast coverage of the synthesis of these natural products is presented for a period from 1990 onwards. The synthesis of all ranges of alkaloids from simple to complex molecules is presented under the groups of alkaloids.

Magnetically recoverable catalytic Co–Co2B nanocomposites for the chemoselective reduction of aromatic nitro compounds

Magnetically recoverable and recyclable Co–Co2B nanocomposites are described for the catalytic and chemoselective reduction of nitroarenes using two different hydrogen sources, sodium borohydride and hydrazine hydrate. Both the systems display an interesting chemoselective reduction switch. The kinetics of reduction of nitroaromatics were studied for the first time and follow nitroreductase enzyme-like kinetics with exceedingly high Kcat (5.2 × 104 s−1) and Kcat/KM (4.4 × 106 M−1 s−1) values, reaching the state of catalytic perfection. The recyclability of the catalyst system was studied by magnetically recovering the nano composite catalyst.

Synthesis of (R)-norbgugaine and its potential as quorum sensing inhibitor against Pseudomonas aeruginosa

(R)-Bgugaine is a natural pyrrolidine alkaloid from Arisarum vulgare, which shows antifungal and antibacterial activity. In this Letter, we have accomplished the simple synthesis of norbgugaine (demethylated form of natural bgugaine) employing Wittig olefination and cat. hydrogenation as the key steps and its biological studies are reported for the first time. The synthesized norbgugaine was evaluated for inhibition of quorum sensing mediated virulence factors (motility, biofilm formation, pyocyanin pigmentation, rhamnolipid production and LasA protease) in Pseudomonas aeruginosa wherein swarming motility is reduced by 95%, and biofilm formation by 83%.

PDC-Mediated Tandem Oxidative–Wittig Olefination

Abstract A convenient tandem oxidative–Wittig olefination of a primary alcohols to α,β-unsaturated compounds using pyridinium dichromate (PDC) is described. GRAPHICAL ABSTRACT