e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
… and absolute configurations of the naturally occurring 3-and 4-methylmuconolactones: X-ray structures of (S)-1-phenylethylammonium salts and an 8-bromo-1-methyl …
AA Freer, GW Kirby, GV Rao, RB Cain
Index: Freer, Andrew A.; Kirby, Gordon W.; Rao, Ghanakota V.; Cain, Ronald B. Journal of the Chemical Society - Perkin Transactions 1, 1996 , # 17 p. 2111 - 2116
(±)-3-Methylmuconolactone (±)-4 is resolved by fractional crystallisation of the (S)-(–)-1- phenylethylammonium salts. The X-ray crystal structures of both salts are determined. Salt A (Fig. 1) gives (S)-(–)-3-methylmuconolactone 4, which is identical to the lactone from fungi. The lactone is converted with bromine into the bromo dilactone 5 and thence with tributyltin hydride into the (–)-1-methylmuconodilactone 6. This dilactone with aqueous sodium ...