From insects to cancer: N-Cyano sulfoximines were evaluated for COX inhibition and antiproliferative activity against a panel of cancer cell lines. The most active compound exhibited potent COX-2 inhibition, some selectivity for COX-2 over COX-1, only slight cytotoxicity towards healthy cells (HaCaT skin cells), and no mutagenic potential (as determined by an Ames assay).

A highly enantioselective Friedel-Crafts reaction catalyzed by a chiral phosphoric acid was developed. N-Boc-protected ethyl trifluoropyruvate imine was activated by 6 mol % of catalyst and reacted with a wide variety of indole derivatives to afford quaternary R-amino acids in excellent yields (up to 99%) and high enantioselectivities (up to 98:2 er).The synthesis of quaternary carbon stereogenic centers remains a challenging goal in organic synthesis. 1 Also, the development of synthetic methods to produce trifluoromethylated compounds in an enantioselective fashion is highly desirable. 2 The catalytic asymmetric Friedel-Crafts (FC) reaction constitutes an important C-C bond-forming transformation, 3 and several examples with trifluoromethyl ketones as electrophiles catalyzed by chiral hydrogen donor catalysts have been published. 4 Directed hydrogen bond interactions represent an important mode of activation for asymmetric organocatalysis. 5

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An efficient, solvent-free protocol for asymmetric Michael additions of α-nitrocyclohexanone to nitroalkenes using thiourea derivatives as hydrogen bonding catalysts has been developed.By performing the organocatalytic reactions in a planetary ball mill, high yields (up to 97%) and excellent enantioselectivities (er up to 98 : 2) were achieved in short reaction times with low catalyst loadings. † Electronic supplementary information (ESI) available: Experimental procedures, results of the reaction condition screening, full characterization of new products, computational and experimental ECD and VCD spectra, and er determinations. See

Scheme1.Chemo-and stereoselective CÀCbondhydrogenationso fa,b-unsaturated ketones. [3b] Scheme2.Ir III /Ir V mechanisms of Brandt and Burgess (ligands abbreviated as N,P and N,C). [5b,c] [a]