Molecules 2006, 11, 169–176 molecules ISSN 1420-3049 http://www.mdpi.org Full Paper Synthesis and Molecular Structure of 6-Amino-3-benzyl- mercapto-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one Long-Chih Hwang 1,*, Chun-Hsien Tu 2, Jung-Hui Wang 3 and Gene-Hsiang Lee 4 1 Faculty of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung City 80708, Taiwan, ROC 2 Department of Psychiatry, Longcyuan Veterans Hospital, Pingtung 912, Taiwan, ROC 3 Department of Pharmacy, Kaohsiung Veterans General Hospital, Kaohsiung City 807, Taiwan, ROC 4 Instrumentation Center, College of Science, National Taiwan University, Taipei City 106, Taiwan, ROC * Author to whom correspondence should be addressed; e-mail:
[email protected] Received: 5 November 2005; in revised form: 10 March 2006 / Accepted: 10 March 2006 / Published: 17 March 2006 Abstract: The title compound 6-amino-3-benzylmercapto-1,2,4-triazolo[3,4-f][1,2,4]- triazin-8(7H)-one (4), molecular formula C11H10N6OS, was obtained by the reaction of 3-amino-2-benzyl-6-hydrazino-1,2,4-triazin-5(2H)-one (3) with carbon disulfide in a water/pyridine mixture. Compound 4 can also be synthesized by reacting 6-amino-3(2H)mercapto-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one (7) with benzyl bromide in methanolic ammonia water. The compound crystallizes in the monoclinic space group P21/c with a = 7.2926(15), b = 14.456(2), c = 11.436(2) Å, β = 105.30(2)°, V 3 3 = 1162.9(4) Å and Z = 4, resulting in a density Dcalc of 1.567 g/cm .