作者:Charles W. Jefford、Krzysztof Sienkiewicz、Steven R. Thornton
DOI:10.1016/s0040-4039(00)76960-7
日期:1994.7
Diethyl L-glutamate hydrochloride (3) was converted to its N-pyrrole derivative 5. Submission of 5 to butyryl chloride in boiling toluene gave the 2-butyryl derivative, and by treatment with NaBH3CN and ZnI2, the 2-butyl analogue 9. Cyclization of 9 with BBr3 afforded (5S)-3-butyl-5-ethoxycarbonyl-5,6-dihydro-8(7H)-indolizinone (10). Hydrogenation of 10 over Pd/C in acidified EtOH gave (3S,5S,9R)-
L-谷氨酸二乙酯盐酸盐(3)转化为其N-吡咯衍生物5。提交5在沸腾的甲苯丁酰氯,得到2-丁酰基衍生物,和通过用NaBH治疗3 CN和ZnI 2,将2-丁基类似物9。用BBr 3环化9,得到(5S)-3-丁基-5-乙氧基羰基-5,6-二氢-8(7H)-吲哚嗪酮(10)。加氢10在酸化的EtOH中,于Pd / C上洗脱,得到(3S,5S,9R)-3-丁基-5-乙氧基羰基吲哚唑烷。通过将后者连续还原为伯醇,形成氯化物,并用氢化三丁基锡,(3S,5R,9R)-3-丁基-5-甲基吲哚并咪唑或(-)-单mor胺进行还原脱氯。从3中提取,收率为25%。