Steiner Bohumil, Langer Vratislav, Koós Miroslav
Institute of Chemistry, Centre of Excelence GLYCOMED, Slovak Academy of Sciences, Bratislava, Slovakia.
Carbohydr Res. 2009 Oct 12;344(15):2079-82. doi: 10.1016/j.carres.2009.06.031. Epub 2009 Jun 26.
The formation of (4R)-4-carbamoyl-4-[(4R)-3-O-benzyl-1,2-O-isopropylidene-beta-l-threofuranos-4-C-yl]-oxazolidin-2-one instead of expected imidazolidin-2,4-dione (hydantoin) derivative from 5-amino-5-cyano-5-deoxy-3-O-benzyl-1,2-O-isopropylidene-alpha-d-glucofuranose or 3-O-benzyl-1,2-O-isopropylidene-alpha-d-xylo-hexofuranos-5-ulose under Bucherer-Bergs reaction conditions is reported. Single crystal X-ray diffraction data revealed that (3)T(4) is the prefered conformation for the furanose ring, while E(2) and (2)T(1) conformations are adopted by the 1,3-dioxolane and 2-oxazolidinone five-membered rings, respectively.
报道了在布赫尔-贝格斯反应条件下,由5-氨基-5-氰基-5-脱氧-3-O-苄基-1,2-O-异亚丙基-α-D-呋喃葡萄糖或3-O-苄基-1,2-O-异亚丙基-α-D-木糖己呋喃糖-5-酮生成了(4R)-4-氨甲酰基-4-[(4R)-3-O-苄基-1,2-O-异亚丙基-β-L-苏型呋喃糖-4-C-基]-恶唑烷-2-酮,而非预期的咪唑烷-2,4-二酮(乙内酰脲)衍生物。单晶X射线衍射数据表明,呋喃糖环的优势构象为(3)T(4),而1,3-二氧戊环和2-恶唑烷酮五元环分别采用E(2)和(2)T(1)构象。