Synthesis of 2'-substituted derivatives of neplanocin A (Nucleosides and nucleotides. XLIV).
作者:KIYOFUMI FUKUKAWA、TOHRU UEDAO、TAKAO HIRANO
DOI:10.1248/cpb.31.1582
日期:——
Neplanocin A (1) and N6-benzoylneplanocin A (2) were converted to the corresponding 3', 6'-O-(tetraisopropyldisiloxane-1, 3-diyl)-neplanocin A's (3, 4). The 2'-hydroxy group in 3 and 4 was triflated (5, 6). Nucleophilic displacement of 5 and 6 with a number of nucleophiles (I-, Br-, Cl-, N3-, AcO-, AcS-) in hexamethylphosphoric triamide afforded the corresponding 2' (R)-substituted derivatives in high yields. The 2' (S)-azido derivatives were obtained in a similar manner from arabinoneplanocin A prepared by this method. Adenosine was also converted to 2' (R)-substituted derivatives, including arabinofuranosyladenine, as well as 2' (S)-substituted adenosines. The physical properties of these 2'-substituted derivatives of neplanocin A and adenosine, including nuclear magnetic resonance and circular dichroism spectra, are presented.
Neplanocin A(1)和 N6-苯甲酰基eplanocin A(2)被转化为相应的 3',6'-O-(四异丙基二硅氧烷-1,3-二基)-eplanocin A(3,4)。3 和 4 中的 2'-羟基被三氟化(5,6)。在六甲基磷酸三酰胺中,用多种亲核剂(I-、Br-、Cl-、N3-、AcO-、AcS-)对 5 和 6 进行亲核置换,可以高产率得到相应的 2' (R)-取代衍生物。用这种方法制备的阿糖胞苷 A 也以类似的方式得到了 2' (S)-叠氮衍生物。腺苷也被转化为 2' (R)-取代的衍生物,包括阿拉伯呋喃糖基腺嘌呤,以及 2' (S)-取代的腺苷。文中介绍了这些 2'-取代的肾上腺素 A 和腺苷衍生物的物理性质,包括核磁共振和圆二色光谱。