Search for "tetracyclic-fused" in Full Text gives 3 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116
Beilstein J. Org. Chem. 2016, 12, 1487–1492, doi:10.3762/bjoc.12.145
Beilstein J. Org. Chem. 2012, 8, 1849–1857, doi:10.3762/bjoc.8.213