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 日本极品人妻VIDEOSSEX| 男男野外做爰全过程69| 美女高潮黄又色高清视频免费| 性高湖久久久久久久久AAAAA| 俄罗斯少妇性做爰片| 韩国三级中文字幕HD久久精品| 欧美精品乱码99久久蜜桃| 精品无人区无码乱码毛片国产 | 日韩人妻精品一区二区三区视频 | 浪荡艳妇爆乳JUFD汗だく肉感| 国产熟妇高潮呻吟声| 国产亚洲精品综合一区| 亚洲 自拍 另类小说综合图区| 浪荡人妻共32部黑人大凶器电影| 自拍 亚洲 综合 另类小说| 久久无码人妻精品一区二区三区 | 国产草草影院CCYYCOM| 久久AV色欲AV久久蜜桃麻豆| 国产AV亚洲精品久久久久久小说 | 我要操电影| 日本黄页网站免费大全| 午夜精品久久久久久毛片| 正在播放老肥熟妇露脸| AAA级久久久精品无码片| А√天堂资源官网在线资源| 激情 人妻 制服 丝袜| 精品久久久久久人妻无码中文字幕| 亚洲成a人片77777kkkk| 天天爽夜夜爽夜夜爽| 躁BBB躁BBB躁BBBBBB| 欧美XXXXX高潮喷水| 天堂√最新版中文在线| 黄页网站推广APP天堂| 亚洲日韩AV无码中文字幕美国| 99精品国产在热久久无码| 国产SUV精品一区二区| 人妻丰满熟妇AV无码区| 国产精品偷伦视频免费观看了| 欧美日韩国产精品| 蜜桃AV噜噜一区二区三区| 欧美黑人又粗又大高潮喷水|