3-Hydroxy- and 3-alkoxy-2-sulfanylquinazolin-4(3H)-ones: synthesis and reactions with alkylating and acylating agents
作者:P. S. Khokhlov、V. N. Osipov、A. V. Roshchin
DOI:10.1007/s11172-011-0022-1
日期:2011.1
Reactions of methyl 2-isothiocyanatobenzoate with hydroxylamine and alkoxyamines afforded earlier unknown 3-hydroxy-2-sulfanylquinazolin-4(3H)-one (1a) and 3-alkoxy-2-sulfanylquinazolin-4(3H)-ones (1b,c). Base-catalyzed reactions of compound 1a with alkyl halides were not regioselective, yielding O,S-dialkylation products. In the presence of acetic acid and sodium acetate, compound 1a was alkylated only at the S atom to give 2-alkylsulfanyl-3-hydroxyquinazolin-4(3H)-ones. Selective O-acylation of compound 1a at position 3 yielded 3-acyloxy-2-sulfanylquinazolin-4(3H)-ones.
甲基2-异硫氰基苯甲酸酯与羟胺和烷氧基胺的反应生成了先前未知的3-羟基-2-巯基喹唑啉-4(3H)-酮(1a)和3-烷氧基-2-巯基喹唑啉-4(3H)-酮(1b,c)。化合物1a与烷基卤化物在碱催化下的反应没有区域选择性,生成了O,S-二烷基化产物。在乙酸和乙酸钠的存在下,化合物1a仅在S原子上进行烷基化,得到2-烷基巯基-3-羟基喹唑啉-4(3H)-酮。在3位选择性O-酰化化合物1a,得到了3-酰氧基-2-巯基喹唑啉-4(3H)-酮。