Aid. Alanine et al., BIOSYNTHESIS OF VITAMIN-B-12 - STUDIES OF THE OXIDATIVE AND LACTONE-FORMING STEPS BY O-18-LABELING, Journal of the Chemical Society, Chemical Communications, (14), 1994, pp. 1649-1650
Experiments based on the use of O-18(2) and electrospray mass spectrom
etry show that during the conversion of precorrin-3A 1 into precorrin-
3B 2 or precorrin-4 3 just one atom of oxygen is incorporated.