Structure-activity studies of photoactivated antiviral and cytotoxic tricyclic thiophenes - Marles,R.J.; Hudson,J.B.; Graham,E.A.; Soucy-Breau,C.; Morand,P.; Compadre,R.L.; Compadre,C.M.; Towers,G.HN.; Arnason,J.T. (Photochem Photobiol, 1992)