These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Shapes of benz[a]anthracenes: the crystal and molecular structure of 2-methylbenz[a]anthracene.
    Author: Briant CE, Jones DW.
    Journal: Cancer Biochem Biophys; 1985 Dec; 8(2):129-35. PubMed ID: 3841296.
    Abstract:
    The crystal structure of 2-methylbenz[a]anthracene (2-MBA), the least carcinogenically active of the monomethylbenz[a]anthracenes, has been determined by application of direct methods to single-crystal X-ray diffractometric data and refined by least squares to R = 0.033 (Rw = 0.035). Deviations of the carbon atoms from the mean molecular plane are much smaller than in the rather more active 1-MBA; in 2-MBA, the benzo-ring A is inclined at about 2 degrees to each of the three rings in the anthracene moiety and even the methyl carbon atom is displaced by only 0.07 A from the ring-carbon atom plane of 2-MBA (and by 0.01 A from the ring-A plane). As in other MBA, the shortest C-C bond in this accurately determined structure is at the K-region (C(5)-C(6) = 1.330(3) A) but three other bonds are short; C(8)-C(9) = 1.347(4), C(10)-C(11) = 1.353(3) and the M-region bond C(3)-C(4) = 1.359(4) A (0.003 A longer if corrected for rigid-body librations). The 2-methyl group appears to take up two orientations with one trio of hydrogen positions more favored than the other.
    [Abstract] [Full Text] [Related] [New Search]