Four new isomeric macrolides of combretastatin D-2 congeners named isocorniculatolide A (1), 11-O-methylisocorniculatolide A (2), 11-O-methylcorniculatolide A (3), and 12-hydroxy-11-O-methylcorniculatolide A (4), and the known corniculatolide A (5), arjunolic acid, and maslinic acid were isolated from the CHCl(3) extract of the bark of Aegiceras corniculatum. The structures of the new compounds (1-4) were elucidated by a combination of spectroscopic analysis (1-5), chemical modifications, and single-crystal X-ray analysis (1).

Excolides A-B (1-4) represent the first examples of a new class of secolabdanoids with an unprecedented framework, which were isolated from the stems of Excoecaria agallocha. Their structures were determined by spectroscopic analysis, chemical modifications, CD, and single-crystal X-ray analysis (1 and 4) as excolide A (1), 11-epi-excolide A (2), 11,13-di-epi-excolide A (3), and excolide B (4). In addition, the structure of rhizophorin A (7), a novel bicyclic secolabdanoid, was revised as excolide A (1).

Agallochaexcoerin A (1), a seco-manoyl oxide diterpenoid was metabolised by pathogenic fungus, Aspergillus flavus, in growth media to yield a new metabolite, termed agallochaexcoerin G (2). It was confirmed by using IR, UV, (1)H NMR and HR-ESI-MS techniques. This microbial bioconversion was achieved by unusual dehydration at C-4 position.

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Two new constitutional isomers of ent‐labdane‐type diterpenoids, 1 and 2, with an unusual seven‐membered lactone moiety (i.e., 1), together with two known compounds, 3 and 4, were isolated from the acetone extract of Rhizophora mucronata. Their structures were elucidated as rhizomucronol A and B (1 and 2, resp.) by spectroscopic analyses and chemical evidence. The absolute configuration of 2 was established by applying the Mosher ester procedure.

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-Glucosidase Inhibitory Monoacylated Polyhydroxytriterpenoids from the Fruits of Barringtonia racemosa. -Monoacylated polyhydroxy triterpenoids racemosol C (I) and racemosol D (II) encountered in this study are unusual and exhibit excellent -glucosidase inhibition and moderate cytotoxicity. -(PONNAPALLI*, M. G.; SUKKI, S.; ANNAM, S. C. V. A. R.; ANKIREDDY, M.; TIRUNAGARI, H.; TUNIKI, V. R.; BOBBILI, V. V. P.; Tetrahedron Lett. 56 (2015) 12, 1570-1574, http://dx.