中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 9-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-2-amino-6-azidopurine | 79999-42-1 | C16H18N8O7 | 434.368 |
2',3',5'-三乙酰鸟苷 | 2',3',5'-tri-O-acetyl-guanosine | 6979-94-8 | C16H19N5O8 | 409.356 |
鸟苷 | GUANOSINE | 118-00-3 | C10H13N5O5 | 283.244 |
中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
2-氨基腺嘌呤核苷 | 2-aminoadenosine | 2096-10-8 | C10H14N6O4 | 282.259 |
—— | 9-(β-D-ribofuranosyl)-2,6-diamino-8-bromopurine | 81102-44-5 | C10H13BrN6O4 | 361.155 |
—— | 9-(β-D-ribofuranosyl)-8-(3"-thienyl)-2,6-diaminopurine | —— | C14H16N6O4S | 364.385 |
—— | 9-(β-D-ribofuranosyl)-8-(2"-furyl)-2,6-diaminopurine | —— | C14H16N6O5 | 348.318 |
—— | 9-(β-D-ribofuranosyl)-8-(3"-furyl)-2,6-diaminopurine | —— | C14H16N6O5 | 348.318 |
—— | 9-(β-D-ribofuranosyl)-8-(2"-thienyl)-2,6-diaminopurine | —— | C14H16N6O4S | 364.385 |
Enzymatic deamination of adenosine 1-N-oxide gave 1-hydroxyinosine (2a) which was acetylated and then chlorinated to give 2,6-dichloro-9-(2,3,5-tri-O-acetyl-(β-D-ribofuranosyl)purine (3). Ammonia in dry 1,2-dimethoxyethane converted 3 into 2-chloro-adenosine triacetate (4a). Treatment of 4a with trimethylamine at elevated temperatures in acetonitrile resulted in formation of 2-N,N-dimethylaminoadenosine triacetate (4b). Guanosine (5) was acetylated smoothly by an improved procedure. The resulting triacetate (6) was chlorinated in ∼85% yield to give 2-amino-6-chloro-9-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)purine (7). Treatment of 7 with trimethylamine at ambient temperature for 28 hours gave the 6-N,N-dimethylamino compound (8d). However, potassium fluoride or sodium azide with catalytic quantities of trimethylamine in DMF or acetonitrile gave the 2-amino-6-fluoro (8a) or 2-amino-6-azido (8b) products in yields of greater than 90%.
Treatment of 2,6-diamino-9-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)purine (1c) with tert-butyl nitrite (TBN) in 60% anhydrous hydrogen fluoride/pyridine at −20 °C gave 2-fluoroadenosine triacetate (2) in 48% yield. Analogous treatment of the acetylated 2-amino-6-fluoropurine nucleoside (1a) gave the 2,6-difluoro compound (3a) in 63% yield. Anhydrous ammonia in 1,2-dimethoxy-ethane converted 3a → 2 without ammonolysis of the acetate groups. The overall conversion of 1a → 3a → 2 without isolation of 3a proceeded in 80% yield. Similar diazotization of the 2-amino-6-chloro nucleoside (1b) in HF/pyridine gave the 2-fluoro-6-chloro analogue (3b) in 89% yield. Treatment of 1b with TBN and pyridine hydrochloride in dichloromethane (77%) or TBN and antimony trichloride in 1,2-dichloroethane (84%) gave the 2,6-dichloropurine nucleoside (4b). The latter conditions converted 1a to the 2-chloro-6-fluoro product (4a) in 77% yield. Conversions of 1a and 1b to the 2-bromo-6-fluoro (5a, 67%) and 2-bromo-6-chloro (5b, 78%) analogues were effected using TBN and antimony tribromide in dibromomethane.