| 摘要 |
<p>Novel pyrrolocoumarin derivatives represented by general formula (I), wherein .... represents a single or double bond, R4 and R8 each are hydrogen or C1-4alkyl, R6 is hydrogen or hydroxyl, and R5 and R9 each are hydrogen, hydroxyl, C1-4alkyl or C1-4alkoxy, with the proviso that R6 can only be hydroxyl when .... is a single bond and that R5 and R9 are different from hydroxyl when R6 is hydroxyl, are useful as active ingredients in pharmaceuticals, as colorants and as intermediates. A preferred class of formula (Ia), wherein R4 and R8 each are hydrogen or C1-4alkyl, and R5 and R9 each are hydrogen, hydroxyl, C1-4alkyl or C1-4alkoxy, may be used in pharmaceutical compositions for the photochemotherapy of psoriasis. The compounds of formula (I) can be prepared by a cyclisation reaction according to Pechmann, preferably followed by a dehydrogenation or dehydration reaction to form compounds of formula (Ia). </p> |
