Ensiklopedia Dunia

Technopedia Center

Faculty of Engineering and Computer Science
S1 Informatics S1 Information Systems S1 Information Technology S1 Computer Engineering S1 Electrical Engineering S1 Civil Engineering

faculty of Economics and Business
S1 Management S1 Accountancy

Faculty of Letters and Educational Sciences
S1 English literature S1 English language education S1 Mathematics education S1 Sports Education

Benzopyran - Wikipedia

From Wikipedia, the free encyclopedia

(Redirected from Chromene)

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Benzopyran" – news · newspapers · books · scholar · JSTOR (January 2017) (Learn how and when to remove this message)

Benzopyran
Identifiers

CAS Number	2H-chromene: 254-04-6^Y[PubChem]
3D model (JSmol)	2H-chromene: Interactive image
Beilstein Reference	109871
ChEBI	2H-chromene: CHEBI:35601
ChemSpider	2H-chromene: 8856^N
PubChem CID	2H-chromene: 9211
UNII	2H-chromene: 7U3W6XRV5U
CompTox Dashboard (EPA)	2H-chromene: DTXSID80180051
InChI InChI=1S/C9H8O/c1-2-6-9-8(4-1)5-3-7-10-9/h1-6H,7H2^Y Key: KYNSBQPICQTCGU-UHFFFAOYSA-N^Y
SMILES 2H-chromene: C1=Cc2ccccc2OC1
Properties
Chemical formula	C₉H₈O
Molar mass	132.162 g·mol⁻¹
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references

Benzopyran is a polycyclic organic compound that results from the fusion of a benzene ring to a heterocyclic pyran ring.

According to current IUPAC nomenclature, the name chromene used in previous recommendations is retained; however, systematic ‘benzo’ names, for example 2H-1-benzopyran, are preferred IUPAC names for chromene, isochromene, chromane, isochromane, and their chalcogen analogues.^[1] There are two isomers of benzopyran that vary by the orientation of the fusion of the two rings compared to the oxygen, resulting in 1-benzopyran (chromene) and 2-benzopyran (isochromene)—the number denotes where the oxygen atom is located by standard naphthalene-like nomenclature.

Some benzopyrans have shown anticancerous activity in vitro.^[2]

The radical form of benzopyran is paramagnetic. The unpaired electron is delocalized over the whole benzopyran molecule, rendering it less reactive than one would expect otherwise. A similar example is the cyclopentadienyl radical. Commonly, benzopyran is encountered in the reduced state, in which it is partially saturated with one hydrogen atom, introducing a tetrahedral CH₂ group in the pyran ring. Therefore, there are many structural isomers owing to the multiple possible positions of the oxygen atom and the tetrahedral carbon atom: