5-tri-0-acetyl-2,6-anhydro-L-mannono-and-D-gulonothioamides (5, 6) has been achieved from the corresponding nitriles. The Hantzsch reaction of (5) or (6) with ethyl bromopyruvate afforded the expected thiazoles (7.8) only in a low yield along with furan derivatives (9-11), the formation of which is rationalized by an acid-catalysed rearrangement-elimination process. The some Hantzsch reaction in the presence
                                    从相应的腈类已经实现了3,4,5-三-0-乙酰基-2,6-脱
水-L-
甘露糖基-和-
D-古洛糖基
硫酰胺的大规模合成(5,6)。(5)或(6)与
溴丙酮酸乙酯的Hantzsch反应仅以低收率提供了预期的
噻唑(7.8)以及
呋喃衍
生物(9-11),其形成通过酸催化重排消除而合理化过程。在
碳酸钡存在下的一些Hantzsch反应产生羟基
噻唑啉(16,17)。试图脱
水(16)或(17)与
三氟乙酸酐或
三氟乙酸酐/
吡啶形成pent-1'-enopyranosylthiazoles(18-20)。脱保护的
硫代酰胺(24,25),配有
溴丙酮酸乙酯噻唑(27,28)。将所获得的
噻唑酯(7,8,18-20。27,28)转化到新
噻唑呋林类似物(12,13,21-23)。