Nogi, Keisuke published the artcileAromatic metamorphosis: conversion of an aromatic skeleton into a different ring system, Application of Spiro[fluorene-9,9′-xanthene], the publication is Chemical Communications (Cambridge, United Kingdom) (2017), 53(29), 4055-4065, database is CAplus and MEDLINE.
Recent advances in the area of “aromatic metamorphosis”, where various aromatic compounds, such as dibenzothiophenes, dibenzofurans, and benzofurans, are transformed into a variety of ring systems using a multi-step strategy or ideally in one step has been reviewed.
Chemical Communications (Cambridge, United Kingdom) published new progress about 159-62-6. 159-62-6 belongs to naphthyridine, auxiliary class Other Aromatic Heterocyclic,Spiro, name is Spiro[fluorene-9,9′-xanthene], and the molecular formula is C25H16O, Application of Spiro[fluorene-9,9′-xanthene].
Referemce:
https://en.wikipedia.org/wiki/1,8-Naphthyridine,
1,8-Naphthyridine | C8H6N2 – PubChem