Die Titelverbindungen 3, 5, 7, 9 und 11 werden aus aliphatischen Sulfinsäuren 1 durch Reaktion mit Aldehyden 2 und Amiden, durch Kondensation mit Amidalen 4 oder Amid‐Mannich‐Basen 6 und 8 und durch Reaktion mit α‐Halogenmethylamiden 10 dargestellt.
The reaction of rifamycin S and the quinonic 3-(hydrazonomethyl)rifamycin derivatives with sodium sulfinates under neutral conditions were found to afford the hydroquinone-type 4-O-sulfonyl derivatives of rifamycin. 3-Amino-4-deoxo-4-iminorifamycin S also gave rise to the hydroquinone-type 4-deoxy-4-sulfonylamino derivatives of rifamycin when treated with sodium sulfinates. Under acidic conditions, rifamycin S and 3-bromorifamycin S produced the hydroquinone- and quinone-type 3-sulfonyl derivatives of rifamycin, respectively, by reactions with sodium sulfinates. Some of sodium salts of 4-O-sulfonylrifamycin SV derivatives afforded rifamycin S and sodium sulfinates and/or sodium sulfonates when heated in AcOEt.
在中性条件下,利福霉素 S 和喹诺酮 3-(肼甲基)利福霉素衍生物与亚硫酸钠反应,生成了对苯二酚型 4-O 磺酰基利福霉素衍生物。3-Amino-4-deoxo-4-iminorifamycin S 经亚硫酸钠处理后,也可生成对苯二酚型 4-脱氧-4-磺酰氨基利福霉素衍生物。在酸性条件下,利福霉素 S 和 3-溴利福霉素 S 与亚硫酸钠反应,分别生成对苯二酚型和醌型 3-磺酰基利福霉素衍生物。在 AcOEt 中加热时,4-O-磺酰基利福霉素 SV 衍生物的一些钠盐可生成利福霉素 S 和硫酸钠和/或磺酸钠。
Regioselective quinazoline C2 modifications through the azide–tetrazole tautomeric equilibrium
lines undergo functional group swap when treated with an azide nucleophile: 1) the azide replaces the sulfonyl group at the C4 position; 2) the intrinsic azide–tetrazole tautomeric equilibrium directs the nucleofugal sulfinate from the first step to replace chloride at the C2 position. This transformation is effective with quinazolines bearing electron-rich substituents. Therefore, the title transformations
6-azido-2-sulfonylpurine derivatives with 61-83% yields when treated with sodium azide. Under optimized reaction conditions, the title compounds are obtained in a one-pot process, which involves a sequential treatment of 2,6-dichloropurines with a selected sodium sulfinate and sodium azide. Such a sulfonyl group dance (functional group swap) results from a cascade of SNAr reactions, which are facilitated