The combination of a cinchona-based chiral primary amine and a BINOL-phosphoric acid has been demonstrated as a powerful and synergistic catalyst system for the double Michael addition of isatylidene malononitriles with α,β-unsaturated ketones, to provide the novel chiral spiro [cyclohexane-1,3'-indoline]-2',3-diones in high yields (88-99%) with excellent diastereo- and enantioselectivities (94:6-99:1 dr's, 95-99% ee's).

Considerable interests have been attracted by isosteviol and its derivatives because of their large variety of bioactivities. In this project, a series of novel 15-and 16-substituted isosteviol derivatives were stereoselectively prepared by means of functional interconversions in ring D of the tetracyclic diterpene isosteviol. All compounds synthesized were characterized by analysis of NMR, IR, HR-MS data, and the configurations of 33 and 37 were confirmed by X-ray crystallographic analysis. The antibacterial activities in vitro of these isosteviol derivatives were investigated; the synthetic compounds were more active against Gram-positive than Gram-negative bacteria, and were especially active against Bacillus subtilis. Among them, compound 27 (MIC ¼ 1.56 mg/ml) exhibited the highest antibacterial activity and thus may be exploitable as a lead compound for the development of potent antibacterial agents.

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Two novel amphiphilic L-proline derivatives bearing long alkyl chain on the 4-position via ether bonds, 1a and 1b, have been synthesized and evaluated for the asymmetric direct aldol reaction in organic solvents as well as in water. The catalytic activities with 5 mol% of 1a are better than that of 30 mol% of proline itself being used. Especially, high yields (up to 99%), excellent enantioselectivities (up to 99% ee) and anti-diastereoselectivities (up to 99:1) are achieved in the reactions of aromatic aldehydes and cyclic ketones at room temperature with 5 mol% of 1a in water.

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