通过赫德-莫里反应合成吡咯并[2,3-d][1,2,3]噻二唑-6-羧酸酯。研究N-保护基对环化反应的影响。

Stanetty Peter, Turner Martin, Mihovilovic Marko D

Vienna University of Technology, Institute of Applied Synthetic Chemistry, Austria.

Molecules. 2005 Feb 28;10(2):367-75. doi: 10.3390/10020367.

A route to methyl pyrrolo[2,3-d][1,2,3]thiadiazole-6-carboxylates as potential plant activators and inducers of systemic acquired resistance (SAR) is reported. A synthetic strategy based on cyclization of the thiadiazole ring system utilizing thionyl chloride via the Hurd-Mori protocol as key step was developed. Success of the ring closure reaction turned out to be highly dependent on the nature of the N-protecting group of the pyrrolidine precursor. While electron donors such as alkyl gave only poor conversion to the required 1,2,3-thiadiazoles, an electron withdrawing substituent such as methyl carbamate gave superior yields.

报道了一种合成甲基吡咯并[2,3-d][1,2,3]噻二唑-6-羧酸酯的方法，该化合物可作为潜在的植物激活剂和系统获得性抗性（SAR）诱导剂。开发了一种基于利用亚硫酰氯通过赫德-莫里协议使噻二唑环系统环化的合成策略，该步骤为关键步骤。结果表明，闭环反应的成功高度依赖于吡咯烷前体的N-保护基的性质。虽然烷基等给电子体只能使所需的1,2,3-噻二唑的转化率很低，但吸电子取代基如甲基氨基甲酸酯能提供更高的产率。