5-核糖或木糖亚甲基-2,4-咪唑啉二酮衍生物的合成及其杀菌活性

Synthesis and Fungicidal Activity of D-Ribose and D-Xylose with Hydantion

以1,2:5,6-O-二异丙叉-α-D-呋喃葡萄糖为原料,经过吡啶重铬酸盐(PDC)氧化、NaBH4还原及选择性水解,实现α-D-木糖环向α-D-核糖环的C(3)位羟基构型的转化,然后分别在高碘酸钠氧化作用下得到糖环上C(5)位为醛基的α-D-木糖和α-D-核糖衍生物,它们分别与2,4-咪唑啉二酮-5-膦酸酯及2-硫代-2,4-咪唑啉二酮发生Wittig-Horner反应及Knoevenagel反应,分离得到3对5-核糖或木糖亚甲基-2,4-咪唑啉二酮衍生物顺反异构体,它们的化学结构经1H NMR,IR,MS和X射线单晶衍射确证.初步生物活性测定结果表明:在50μg/mL浓度下,部分目标化合物均对供试菌种显现出一定的抑制活性.

The α-D-ribose and a-D-xylose C（5）-aldehyde derivatives （1 and 2） were prepared through four and two steps using 1,2：5,6-di-O-isopropylidene-α-D-glucofuranose as raw material. Then 1 and 2 reacted with hydantoin phosphonate and 2-thiohydantoin by Wittig-Homer and Knoevenagel reaction to afford 3 pairs of E and Z isomers of target products 3-5. Their structures were elucidated by 1H NMR, 13C NMR, IR, MS and X-ray diffraction. The preliminary bioassay results showed that some of them have certain fungicidal activities against 7 plant pathogens at the concentration of 50 μg/mL.