日本大肚子孕妇交XXX,天天夜碰日日摸日日澡性色AV,女女女女女女BBBBBB毛,岳的大肥屁熟妇五十路99

熱線電話
產(chǎn)品新聞

Synthesis and Crystal Structures of Chiral

Abstract N-(2-Bromopropionyl)-O-benzyl-L-serine (BPBS) was prepared using 2-bromopropionic acid
and N-Boc-O-Bzl-L-serine as the starting reagents. BPBS underwent the intra-molecular ring-closing reac-
tion in DMF/Et
3
N solvent at 80 ℃for 9 h forming a mixture of two non-enantiomers, i.e. (3S,6S)-benzyl-
oxymethyl-6-methyl-morpholine-2,5-dione [(3S,6S)-BMMD] and (3S,6R)-BMMD with a yield of 70%. Two
optically pure enantiomers of BMMD, i.e. (3S,6S)-BMMD and (3S,6R)-BMMD were obtained via 4 opera-
tion circles of “solution-partial recrystallization” by means of a differential recrystallization method using
ethyl acetate as a solvent. The single crystals of the two isomers of BMMD were grown from ethyl acetate at
room temperature. The fine molecular structures of the two isomers were determined by X-ray diffraction
analysis of the single crystals.
Keywords (3S,6S)-benzyloxymethyl-6-methyl-morpholine-2,5-dione; (3S,6R)-benzyloxymethyl-6-methyl-
morpholine-2,5-dione; resolution; optical isomer; crystal structure


下一篇
日本大肚子孕妇交XXX,天天夜碰日日摸日日澡性色AV,女女女女女女BBBBBB毛,岳的大肥屁熟妇五十路99 亚洲国产AV无码男人的天堂| 亚洲 欧美 激情 小说 另类| 国产精品久久久久久久9999| 亚洲女人被黑人巨大进入| 中文字幕精品一区二区精品 | 免费人成自慰网站| 精品无码一区二区三区在线| 精品亚洲综合成人网| 国产精品久久久久久爽爽爽| 艳妇乳肉豪妇荡乳AV无码福利 | 国产精品丝袜黑色高跟鞋| 97伦伦午夜电影理伦片| 亚洲永久无码7777KKK| 丁香花在线影院观看在线播放| 成人欧美日韩一区二区三区| 国产精品久久国产精麻豆99网站| 国产精品久久久久久吹潮| 中国熟女高潮视频| 少妇真人直播APP| 国产精品日日做人人爱| 国产欧美一区二区精品性色| 亚洲一区精品无码色成人| 黑料每日大赛在线吃瓜| 无码人妻精品一区二区三区欧美色涩| 免费看一区二又大又粗又黄的| BXBXBXBX性老熟妇XXX| 精品国产一区二区三区AV性色| 无码国产精品一区二区高潮| 农村熟女XXXXHD做受| 亚洲AV永久无码国产精品久久| 欧产日产国产精品精品| 玖玖视频这里只有精品| 亚洲无AV在线中文字幕| 国产精品精华液网站| 国产精品18久久久| 袖珍人与大黑人性视频| 国产精品毛片一区二区| 一区二区乱子伦在线播放| 男生把手放进我内裤揉摸好爽| 色88久久久久高潮综合影院| 国产精品人成在线播放新网站|