| 摘要 |
<p>The invention comprises compounds of the general formula <FORM:0997179/C2/1> wherein R1 represents a chlorine, bromine or iodine atom or an alkyl group, R2 represents a nitro group where there is an adjacent benzyloxy group or represents an arylazo or amino group when there is an adjacent hydroxy group or may be absent or represent an acylamino group where there is an adjacent benzyloxy group and R3 represents a benzyl group, and wherein the broken lines denote that R1 and (subject to the foregoing proviso) R2 are optional, and the bonds radiating from the carbon atom, marked with an asterisk are appropriate to an alphaglycoside, and the preparation thereof, and of compounds wherein R2 is absent or represents an acylamino group when there is an adjacent hydroxy group, by opening the cyclocarbonate ring of a 2,3-cyclocarbonate-alphaglycosidocoumerin of the formula <FORM:0997179/C2/2> by treatment with ammonia or an alkylamini or dialkylamini. When the reaction is carried out in the presence of sodium metal, benzyloxy groups in the 4-position are converted to hydroxy groups.</p> |
