in long-term experiments such as the studies on tumor transmission to healthy mice by injection of sensitized ehrlich ascites cells , or on the survival of e. coli cells , in which dna repair is active , 4'-methylangelicin derivatives appeared to be several times more active than angelicin and 4,5'-dimethylangelicin , and sometimes also more active than psoralen , a well-known , effective and cross-linking furocoumarin .
C0016072
psoralen
C0016859
furocoumarin