Bacterial Carotenoids. LIII. C50-Carotenoids. 19. Absolute Configuration of Sarcinaxanthin and Sarcinaxanthin mono-beta-D-glucoside. Isolation of Sarcinaxanthin Diglycoside.

Abstract
By improved 1H NMR data, sarcinaxanthin is shown to be centrosymmetric with terminal methylene groups in substituted .gamma.-rings, consistent with IR and MS [mass spectroscopy] data. (2R,6R,2''R,6''R)-chirality for sarcinaxanthin follows from CD [circular dichroism] and 1H NMR data in comparison with appropriate models. Sarcinaxanthin occurs in Sarcina lutea at least partly esterified with a C9H11COOH acid. A previously characterized C50-carotenoid .beta.-D-glucoside is by 1H NMR and CD data shown to be sarcinaxanthin mono-.beta.-D-glucoside. A dihexoside, presumably sarcinaxanthin diglucoside, was isolated for the 1st time. Previously characterized less polar carotenoids were not present in 3 batches. CD data for sarcinaxanthin and decaprenoxanthin are discussed in relation to preferred conformations.