CAS No 50-32-8 , benzo[a]pyrene

Title: Benzo[a]pyrene
CAS Registry Number: 50-32-8
Synonyms: 3,4-Benzpyrene
Molecular Formula: C20H12
Molecular Weight: 252.31
Percent Composition: C 95.21%, H 4.79%
Literature References: Formerly called 1,2-benzpyrene. Occurs in coal tar, q.v. Isoln by fractionation: Cook et al., J. Chem. Soc. 1933, 395; by adsorption and fluorimetric determn: Hieger, Am. J. Cancer 29, 705 (1937); Winterstein et al., Z. Physiol. Chem. 230, 158, 169 (1934); Naturwissenschaften 22, 237 (1934). Synthesis from pyrene and succinic anhydride: Cook, Hewett, J. Chem. Soc. 1933, 398; Fieser, Fieser, J. Am. Chem. Soc. 57, 782 (1935); Winterstein et al., Ber. 68, 1079 (1935); Fieser et al., J. Am. Chem. Soc. 57, 1509 (1935). Absorption spectrum: Mayneord, Roe, Proc. Roy. Soc. London A152, 299 (1935). Review: Clar, Polycyclic Hydrocarbons Vol. 1 & 2 (Academic Press, New York, 1964). Review of carcinogenicity studies: IARC Monographs 3, 91-136 (1973). Inhibition of the mutagenicity of the ultimate carcinogenic metabolite of benzo[a]pyrene by ellagic acid: A. W. Wood et al., Proc. Natl. Acad. Sci. USA 79, 5513 (1982). Study of the reaction between this metabolite (benzo[a]pyrene-7,8-diol 9,10-epoxide) and ellagic acid: J. M. Sayer et al., J. Am. Chem. Soc. 104, 5562 (1982). Review: D. H. Phillips, Nature 303, 468-472 (1983). Review of toxicology and human exposure: Toxicological Profile for Polycyclic Aromatic Hydrocarbons (PB95-264370, 1995) 487 pp.
Properties: Yellowish plates, needles from benzene + methanol, mp 179-179.3°. Crystals may be monoclinic or orthorhombic. bp10 310-312°. Violet fluorescence of dil benzene solns: Hieger, loc. cit. Soluble in benzene, toluene, xylene; sparingly sol in alc, methanol. Practically insol in water.
Melting point: mp 179-179.3°
Boiling point: bp10 310-312°
CAUTION: This substance is reasonably anticipated to be a human carcinogen: Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-220.