The absolute configuration for inthomycin C: revision of previously published work with a reinstatement of the (3R)-configuration for (-)-inthomycin C.

Stereochemical evidence is presented to demonstrate that (-)-inthomycin C has (3R)- and not (3S)-stereochemistry. Careful reappraisal of the previously published work2-5 now indicates that the Hatakeyama, Hale, Ryu, and Taylor teams all have synthesized (-)-(3R)-inthomycin C. The newly measured [α]D of pure (-)-(3R)-inthomycin C (98% ee) is -7.

Formal [4 + 1]-cycloaddition of homopropargyl alcohols to diazo dicarbonyl compounds giving substituted tetrahydrofurans.

A novel formal [4 + 1]-cycloaddition of readily available homopropargyl alcohols with diazo dicarbonyl compounds is described, which involves tandem O-H insertion/Conia-ene cyclization under cooperative Rh(II)/Zn(II) catalysis. This reaction provides easy access to various substituted tetrahydrofurans and exhibits complete E-selectivity in the case of nonterminal alkynes.

α-Isocupreine, an enantiocomplementary catalyst of β-isocupreidine.

Complementary chemistry! α-Isocupreine (-ICPN) was synthesized for the first time in one step from quinine by treatment with CF3SO3H (see scheme). This compound serves as an enantiocomplementary catalyst to β-isocupreidine (β-ICD) in the Morita–Baylis–Hillman reaction.

Total synthesis of (-)-cinatrin C1 based on an In(OTf)3-catalyzed Conia-Ene reaction.

The stereocontrolled total synthesis of (-)-cinatrin C1, a phospholipase A2 inhibitor, has been accomplished. The key feature includes the stereoselective construction of the highly substituted tetrahydrofuran core by In(OTf)3-catalyzed Conia-ene reaction of the oxygen-tethered acetylenic malonic ester followed by dihydroxylation with concomitant lactonization.