As a continuation of our efforts directed towards the development of anti-diabetic agents from natural sources, piplartine was isolated from Piper chaba, and was found to inhibit recombinant human ALR2 with an IC50 of 160 µM. To improve the efficacy, a series of analogues have been synthesized by modification of the styryl/aromatic and heterocyclic ring functionalities of this natural product lead. All the derivatives were tested for their ALR2 inhibitory activity, and results indicated that adducts 3c, 3e and 2j prepared by the Michael addition of piplartine with indole derivatives displayed potent ARI activity, while the other compounds displayed varying degrees of inhibition. The active compounds were also capable of preventing sorbitol accumulation in human red blood cells.

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A practical and efficient protocol for the hydroboration of aldehydes and ketones using a pinacolborane and alkyl lithium system is demonstrated. A systematic evaluation showed that 1 mol % n-butyllithium afforded catalyzed hydroboration of aldehydes and ketones in a short reaction time under ambient conditions. Excellent yield, functional group tolerance, short reaction time, low catalyst loading, and gram-scale synthesis are the salient features of the proposed protocol.

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Thermally expandable microspheres (TEMs) were synthesized via suspension polymerization using acrylonitrile as the major monomer. Methyl methacrylate and methacrylonitrile were used as supporting co-monomers, and 1,4-butanediol dimethacrylate was used as a crosslinking agent. In addition, cinnamonitrile (CN) and diethyl fumarate (DEF) were investigated as monomers to improve the expansion performance of the TEMs. However, the expandability of the TEMs using CN was diminished. When TEMs were prepared with DEF as the crosslinking agent, the expandability was highly affected. From the thermomechanical analysis of TEMs with various crosslinking agents, DEF showed better performance as crosslinking agent, yielding increased expansion properties. This is the first report using DEF as a TEM crosslinking agent.

As part of pharmacological-phytochemical integrated studies on medicinal plants from Indian flora, costunolide (1) and dehydrocostus lactone (2), were isolated as major phytochemicals from Saussurea lappa, a plant traditionally used in different Asian systems of medicine. A series of 1,4-disubstituted-1,2,3-triazoles conjugates were synthesized through diastereo selective Michael addition followed by regioselective Huisgen 1,3-dipolar cycloaddition reactions. All these triazolyl derivatives (5a-5j) & (7a-7j) were well characterized using modern spectroscopic techniques and evaluated for their anticancer activity against a panel of five human cancerous celllines. The results indicated that all the analogs displayed moderate cytotoxic activity.

A series of piplartine derivatives were synthesized via Baylis-Hillman reaction and evaluated for anticancer and antibacterial activities. The cytotoxicity of these compounds was examined in two different human tumor cell lines, IMR-32 and HeLa. The antibacterial activity was examined in Staphylococcus aureus and Pseudomonas aeruginosa. The results showed that compounds 2b, 2e, and 2j were found to be the most active compounds, which displayed line no cytotoxicity, but G2-M cell cycle arrest in tumor cells, and showed cytostatic effects in bacteria.