| 摘要 |
<p>Ribonucleoside 5'-nitrates of formula (I) (where R is (Ia) or (Ib) in which R1 is O or NH, R2 is H, CH3, F, Cl, Br, I or NO2, R3 is H, OH, NH2, F, Cl, Br, or I, R4 is OH, NH2, 1-4C alkoxy, or mono- or di(1-4C alkyl) amino, and R5 is H, F, Cl, Br, I or No2; and Y and Z are H oR is not >7 C acyl or Y + Z is CR6R7 in which R6 and R7 are H, 1-4C alkyl or 6-10C aryl and one of R6 and R7 may also be 2-8C dialkylamino, pyrrolidino, piperidino or morpholino) and their physiologically innocuous salts (e.g. 5'-0-nitro-adenosine) are new cpds. which may be prepd. by treating a cpd. of formula (II), (where W and X are is not >7C acyl or W + X is CR6R7) with an O-nitrating agent (pref. an acyl nitrate, a nitronium salt or N2O5) in practically anhydrous medium at - 70 to +30 degrees C . and opt. selectively hydrolysing the 5'-nitrate obtd. (I) reduced the oxygen requirement of heart muscle and increase tolerance to anoxia; they are therefore useful in the treatment of e.g. coronary insufficiency. Since the nitrate ester function is relatively stable towards acidic and alkaline hydrolysis but can readily be displaced by other nucleophilic reagents, (I) are also useful as intermediates in pyrimidine and purine nucleoside chemistry.</p> |
