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An efficient and concise stereoselective synthesis towards the antimalarial (−)‐Gomphostenin, starting with the enantiomerically pure Wieland–Miescher ketone, is reported. The key transformations of the convergent synthesis involved a stereoselective reductive allylation, Palladium‐catalyzed Saegusa–Ito oxidation, Babler–Dauben oxidative rearrangement, and Wittig olefination reactions. The structure and absolute stereochemistry were determined by X‐ray analysis.

A variety of novel quinoline derivatives (6-phenyl-6 H-chromeno [4,3- b] quinoline) have been prepared by using 4-chloro-2-phenyl-2 H-chromene-3-carbaldehyde and various substituted of aromatic anilines as starting materials. This is the first example on the preparation of quinolines through this novel method. And the resulting quinoline derivatives further structure evolution is leads to an anti cancer agents. Our preliminary data of model compound (7i) on three cancer cell lines (B16F10, MCF7 and A549) suggested decent anticancer activity on two cell lines (B16F10 and MCF7) with IC50 values of 14.8 and 21.32 μM, respectively. This method is operationally simple and works with a diverse range of substrates.

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Novel 2,3-dihydrofuran derivatives were synthesized through a tandem Knoevenagel-Michael cyclization in good yield by reacting α-tosyloxy ketone, 5,5-dimethyl-1,3-cyclohexanedione, and various aldehydes in the presence of phthalazine in acetonitrile. These compounds were subjected to in vitro antibacterial screening against eight micro-organisms by using diffusion method and also in vitro cytotoxicity screening against four human cancerous cell lines by applying MTT assay. Some of the compounds showed impressive activities.

A highly stereoselective and an efficient approach for studies towards the synthesis of thermolide-6' has been described. The salient features of the synthesis are the utilization of desym-metrization protocol, Barton-McCombie deoxygenation and CÀC bond formation from an aldol reaction.

A variety of novel thiazolidine derivatives (2-thioxothiazolidin-4-one and thiazolidine-2, 4-dione derivatives) have been prepared by using 2,4-diphenyl-2Hchromene-3-carbaldehyde and its derivatives as starting materials. This is the first example of the preparation of thiazolidine derivatives through this novel method. Structure evolution of the resulting thiazolidine derivatives leads to anticancer agents. Our preliminary data for some model compounds on three cancer cell lines (MCF7, A549 and B-16) suggested reasonable anticancer activity against the A549 and B-16 cell lines, with IC 50 values of 20.7 and 20.4 µM, respectively. This method is operationally simple and works with a diverse range of substrates.

The stereoselective synthesis of (4S,6S)-6-hydroxy-4-undecanolide, a major pheromone component in the secretion of Idea leuconoe has been accomplished employing Prins cyclization to produce anti-1,3-diols and hydroboration/oxidation of terminal olefin to introduce primary alcohol as the key steps.