Vitamine coined in 1912 CHOH HO+H CH3 HO+H OH N HO+H s CI H3C NH NH H2C Vitamin b Vitamin b O H COH COHn V B3;V v bus HOC 0 烟酸;烟酰胺 DQQVitamine coined in 1912 N CO2HN CO2H HO2C O O H DQQ CH2OH HO H HO H HO H N N NH N O H O 3C H3C Vitamin B2 + Cl￾Vitamin B1 N N N S NH2 CH3 OH CH3 V B3 ; V B6 ; V B12; 烟酸; 烟酰胺