Three isomeric 6-amino-3,6-dideoxyhexono-1,6-lactams of D-ribo (1a), L-lyxo (2a) and L-arabino (3a) configuration were synthesized via the corresponding 6-azido-3,6-dideoxyhexoses starting from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose. Conformation of lactams 1a, 2a and 3a and their tri-O-acetyl derivatives 1b, 2b and 3b was studied using NMR spectroscopy. CD spectra of the lactams 1a-3a, together with the D-xylo diastereoisomer 4a, were measured and interpreted according to semiempirical rules. NMR and CD measurements confirmed the chair conformation with an equatorial substituent on C-2 as prevailing for the all measured lactams.
通过相应的6-
叠氮-3,6-二去氧己糖起始合成了D-
核糖 (
1a), L-
赖氨糖 (
2a) 和 L-
阿拉伯糖 (
3a) 构型的三种同分异构体6-
氨基-3,6-二去氧
己内酯。利用NMR光谱研究了内酯
1a,
2a 和
3a 以及它们的三-
O-乙酰衍
生物 1b,
2b 和
3b 的构象。测量并根据半经验规则解释了内酯
1a-
3a 和 D-
木糖 异构体
4a 的CD光谱。NMR和CD测量证实了所有测量的内酯都具有在C-2上的赤道取代基的椅状构象。