(~(14)C-三唑基)-多效唑的合成

用相转移催化法标记合成了植物生长延缓剂1-对氯苯基-2-(5-(14)~C)-1,2,4-三唑-1-基]4,4-二甲戊-3-醇((14)~C-多效唑)。其步骤包括在相转移催化剂PEG800的存在下,(5-(14)~C)-1,2,4-三唑与一氯片呐酮在乙酸乙酯溶液中反应,生成(5-(14)~C)-α-三唑基片呐酮,后者在苯溶液中再与对氯氯苄反应,生成(14)~C-三唑酮,最后在甲醇溶液中用硼氢化钠还原得到(14)~C-多效唑。其总放化收率为20.9％(以(14)~C-三唑计),放化纯度大于99％。

SYNTHESIS OF ( C-14-TRIAZOL)-PACLOBUTRAZOL

1-p-chlorophenyl-2-(5-C-14) -1, 2, 4-triazol-l-yl-4, 4-dimethyl-pentan -3-01 ( Paclobutrazol) (1) was labelled by phase transfering method. The procedure involved the interaction of (5-C-14)-1,2,4-triazol with 1-chlc-ropinacolone in ethyl acetate to produce ( C-14 )-triazotylpinacolone ( 2). Then, (C-14)-triazotylpinacolone was reacted with p-chlorobenzyl ha-lide to produce (C-14)-triazolyl ketone in benzene (3), and finally(C-14) -triazolyl ketone was reduced by NaBH4 in methanol to give C-14-Paclo-butrazol.Chemical yield was 52%, radio-chemical yield was 20.9%.HPLC and TLC analysis of the final product in methanol solution showed the radiochemical purity to be not less than 99%.