Five-Membered Rings One Heteroatom

Current work is focused on the benzoheteropines with the fused pyrrole (or indole), thiophene or furan rings, i.e., ortho-fused 6 + 7 + 5 ring systems with carbons only on the six-membered ring, one heteroatom on the five-membered ring and one or more heteroatoms on the seven-membered ring. The variety of heteroatoms is limited to nitrogen, oxygen and sulfur. Several examples of the related cyclic systems with the other heteroatom distribution or peri-fusion are briefly summarized in Section 4.3. The current first specialized review covers synthetic, reactivity and structural aspects reported from the late 1989 until 2007. 

Structure of Five-membered Rings with One Heteroatom... 

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