derivatives 2d. Anthracene-9-sulfonamide (6) is readily available by sulfonation and chlorination of anthracene, and condenses with aldehydes [RCHO; R = Ph, 4-FC6H4, 4-MeOC6H4, 4-NCC6H4, 2-furyl, (E)-styryl], e.g. in the presence of TiCl4/Et3N, to yield imines 7a–7f, which after addition of tert-butoxycarbonylmethylzinc bromide give protected amino acids 8a–8f; however, 8f cyclizes to the sultam 9via a spontaneous
Reformatsky试剂叔丁氧基羰基甲基
溴化锌可通过
苯甲醛二甲基
乙缩醛与甲磺酰胺,
甲苯-4-磺酰胺,4-(甲氧基羰基)苯磺酰胺和磺酰胺缩合生成的N-磺
酰亚胺类化合物,例如1a-1d,可提高收率。β-
氨基酸2a–2d。对于2b和2c,N-脱保护以还原性(Na-
萘;低产率)发生,或者对于磺酰胺衍
生物2d以
水解方式(回流
吡啶水溶液;在叔丁酯酸
水解后
氨基酸3a的产率为76%)发生。
蒽9-磺酰胺(6)很容易通过
蒽的磺化和
氯化得到,并与醛缩合[RCHO; R = PH,4-FC 6 H ^ 4,4-MeOC 6 H ^ 4,4-NCC 6 ħ 4,2-
呋喃基,(ë) -
苯乙烯基],例如在的TiCl存在4 / ET 3 N,到屈服
亚胺7a-7f,在加入叔丁氧基羰基甲基
溴化锌后,得到保护的
氨基酸8a-8f;然而,8F环化到磺内酰胺9经由自发的分子内Diels-Alder反应。N-
蒽-9-磺酰基的还原裂解