A Convenient Method for the Synthesis of 2′,3′-Didehydro-2′,3′-Dideoxy Nucleosides
作者:Erwin Dorland、Pawel Serafinowski
DOI:10.1055/s-1992-26141
日期:——
9-(2,3-Dideoxy-β-D-glyceropent-2-enofuranosyl)adenine (2′,3′-didehydro-2′,3′-dideoxyadenosine, 9a), 9-(2,3-dideoxy-β-D-glyceropent-2-enofuranosyl)hypoxanthine (2′,3′-didehydro-2′,3′-dideoxyinosine, 9b) and 4-amino-7-(2,3-dideoxy-β-D-glyceropent-2-enofuranosyl)pyrrolo[2,3-d]pyrimidine (2′,3′-didehydro-2′,3′-dideoxytubercidin, 9c) were prepared via a free radical β-elimination of bromo and phenoxy(thiocarbonyl) leaving groups from appropriate 5′-O-(2-acetoxyisobutyryl)-2′(3′)-phenoxy(thiocarbonyl)-3′(2′)-bromo derivatives 6, 7 of adenosine (1a), inosine (1b) and tubercidin (1c) with tributyltin hydride and subsequent deprotection of the resulting 5′-O-(2-acetoxyisobutyryl)-2′,3′-didehydro-2′,3′-dideoxynucleosides 8a, 8b and 8c, respectively.
通过自由基β-消除反应,从适当的5′-O-(2-乙酰氧异丁酰基)-2′(3′)-苯氧(硫羰基)-3′(2′)-溴代衍生物6、7中去除溴和苯氧(硫羰基)离去基团,制备了9-(2,3-二脱氧-β-D-甘油戊-2-烯呋喃糖基)腺苷(2′,3′-二脱氢-2′,3′-二脱氧腺苷,9a)、9-(2,3-二脱氧-β-D-甘油戊-2-烯呋喃糖基)次黄嘌呤(2′,3′-二脱氢-2′,3′-二脱氧肌苷,9b)和4-氨基-7-(2,3-二脱氧-β-D-甘油戊-2-烯呋喃糖基)吡咯并[2,3-d]嘧啶(2′,3′-二脱氢-2′,3′-二脱氧结核菌素,9c)。这些化合物分别由腺苷(1a)、肌苷(1b)和结核菌素(1c)与三丁基锡氢化物反应,然后分别对得到的5′-O-(2-乙酰氧异丁酰基)-2′,3′-二脱氢-2′,3′-二脱氧核苷8a、8b和8c进行脱保护。