In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called Halogen-substituted products of furfural, published in 1933, which mentions a compound: 2689-65-8, Name is 5-Iodo-2-furaldehyde, Molecular C5H3IO2, Synthetic Route of C5H3IO2.
Furfural diacetate (I) and Br in CHCl3 give 10% of sym-bromofurfural (2-bromo-5-formylfuran), b16 112°, m. 85°; PhNH2 in 50% AcOH gives a characteristic orange-red color; oxime, m. 101°; semicarbazone, m. 215° (corrected, decomposition); phenylhydrazone, m. 80-5°. The di-Et acetal and diacetate could not be prepared Concentrated EtOH-KOH gives bromopyromucic acid. Improved directions are given for the preparation of tetraiodofuran (67% yield). I in AcOH and Hg(OAc)2 give 82% of a trimercuriacetate compound, containing free Hg(OAc)2 which cannot be removed without decomposition of the Hg compound With 0.35% EtOH-HCl there results 86% of the trimercurichloride, which reacts with I in Et2O to give, among other products, sym-iodofurfural, m. 110°.
As far as I know, this compound(2689-65-8)Synthetic Route of C5H3IO2 can be applied in many ways, which is helpful for the development of experiments. Therefore many people are doing relevant researches.
Reference:
1,8-Naphthyridine – Wikipedia,
1,8-Naphthyridine | C8H6N2 – PubChem