A Novel Octahydropyridobenzothiazepine Metabolite in Human Urine: Biomimetic Formation from the Melanogen 5-<i>S</i>-Cysteinyldopa and Formaldehyde via a Peculiar Sulfur-Controlled Double Pictet−Spengler Condensation
作者:Paola Manini、Marco d'Ischi、Giuseppe Prota
DOI:10.1021/jo991969c
日期:2000.7.1
4-thiazepine moiety. Under physiologically relevant conditions, i.e., in 0.1 M phosphate buffer pH 7.4 and at 37 degrees C, the 7,8-tetrahydroisoquinoline 5 was the sole detectable intermediate in the formation of 2. N-Acetylcysteinyldopa (4) reacted likewise with formaldehyde to give the 7, 8-dihydroxytetrahydroisoquinoline 6. The anomalous regiochemistry underlying formation of 5 and 6 was rationalized