In the present paper, we report an efficient total synthesis of a marine alkaloid, rigidin E. The key tetrasubstituted 2-amino-3-carboxamidepyrrole intermediate was synthesized by cascade Michael addition/intramolecular cyclization between N-(2-(4-(benzyloxy)phenyl)-2-oxoethyl)methanesulfonamide and 3-(4-(benzyloxy)phenyl)-2-cyano-N-methylacrylamide. Subsequent carbonylation with triphosgene ca...

An unprecedented organocatalytic enantioselective formal synthesis of bromopyrrole alkaloid natural products is reported. An organocatalytic aza-Michael addition using pyrroles as the N-centered nucleophile is utilized as the enantioselective step to construct the nitrogen-substituted stereogenic carbon center in bromopyrrole alkaloids in good yield and excellent enantioselectivity. The aza-Mic...

Objective: The aim of the present work was to assess the total phenolic content (TPC), total flavonoid content (TFC), and total alkaloid content (TAC) of crude hydro-methanolic seed extract of Abrus precatorius L. which is one of the beautiful seed bearing plant belonging to family Fabaceae and used extensively in many Ayurvedic preparations with significant therapeutic significance. Methods: T...

We report the first total synthesis of oxydimurrayafoline via nucleophilic substitution at the benzylic position at C-3 of the carbazole framework.

In 1997, Kobayashi and co-workers disclosed the isolation of ( )-nakadomarin A (1, Scheme 1) from an Okinawan marine sponge Amphimedon sp. Its unique 8/5/5/5/15/6 hexacyclic full-ring structure containing four stereogenic centers and an imbedded furan was shown with extensive NMR spectroscopic analyses including NOE and proton coupling data. The biological properties of 1 range from prominent c...