5-(1H-Purin-6-ylthio)pentanoic acid 5-(6-Purinylthio)valeric acid 5-(Purin-6-ylthio)valeric acid 6-(4-Carboxybutyl)mercaptopurin 608-12-8 Buthiopurin Buthiopurine Citogran Cytogran NSC 130678 Pentanoic acid, 5-(1H-purin-6-ylthio)- (9CI) Valeric acid, 5-(purin-6-ylthio)-