Angular furocoumarins havebeen obtained from 6-hydroxy-4-methylcoumarin via
substitution in the 5-position, despite any steric hindrance by the 4-methyl group as …

The method, described in earlier papers of this series1 3and developed for the synthesis of
alkyl-substituted psoralenes, has been successfully applied to the synthesis of an …

8-Amino-4, 5'-dimethylpsoralene (Via) has been synthesized by a method involving the
Claisen rearrangement of 8-acetamido-7-allyloxy-4-methylcoumarin (lib). Heating in …

(4) L. Musajo, G. Rodighiero, G. Caporale, and C. Antonello; Farmaco {Pavia) Ed. Sci., 13,
355-362 (1958), report that the introduction of a phenyl substituent on the furan ring of …

A synthesis of psoralene and alkylpsoralenes from 2-bromoresorcinol is described.
Treatment of 2-iodomethyl-8-oxo-2, 3-dihydro-8H-furo [2, 3. h][l] benzopyran with sodium …

Surprisingly, the results were not the same as in the 7-hydroxycoumarin series. A linear
furocoumarin was not obtained owing to the formation of an oxazolo-coumarin (Via) during …

The synthetic method described in Part I1 of this series has been utilized for the synthesis of
several psoralenes bearing alkyl substituents in the 3-, 4-, 8-, or 5'-positions. 2 Wide …

Practical syntheses of psoralen (IVb) and 3-methylpsoralen (IVc) fromß-resorcylaldehyde
are described. Bromination of ethyl (2-formyl-5-methoxyphenoxy) acetate gave the 4 …

Earlier syntheses offurocoumarins have involved the use of the Pechmann condensation of
hydroquinone (Ia) with acetoacetic ester to obtain 6-hydroxy-4-methylcoumarin (Ha). 1 As an …

Furocoumarins are an important group of natural bioregulators. These compounds are
mainly derivatives of the widely distributed natural linear furocoumarin psoralen. Its angular …