SEARCH Articles Figures Tables Condensed thiophene systems, tetra- and pentacyclic Klemm, L. H., Syntheses of Tetracyclic and Pentacyclic Condensed Thiophene Systems Of tetracyclic and pentacyclic condensed thiophene systems Pentacycles Pentacyclic and Higher Systems Synthesis, of tetracyclic and pentacyclic condensed thiophene systems