Synthesis 2003(3): 0375-0382
DOI: 10.1055/s-2003-37353
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of All Stereoisomers and Some Congeners of Isocytoxazone

Zdenko Hameršaka, Dragan Šepaca, Dinko Žiherb, Vitomir Šunjić*a
a Ruđer Bošković Institute, Bijenič ka c. 54, POB 180, 10002 Zagreb, Croatia
Fax: +385(1)4680195; e-Mail: sunjic@rudjer.irb.hr;
b PLIVA Research and Development Institute, Ul. Baruna Filipovića 25, 10000 Zagreb, Croatia
Further Information

Publication History

Received 23 October 2002
Publication Date:
19 February 2003 (online)

Abstract

cis-Isocytoxazone 2a and trans-isocytoxazone 2b, structural isomers of the antiasthmatic agent cytoxazone (-)-1, and their 5-substituted congeners 23-28 have been prepared. Aldol reaction of para-substituted benzaldehydes with 7-chloro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one, followed by separation of diastereomeric racemates afforded 3-10. Acid-catalyzed 1,4-benzodiazepine ring opening, and transformation of the methyl esters of β-aryl-β-hydroxy-α-amino acids (11-16) via 4-methoxycarbonyl derivatives of 1,3-oxazolidin-2-one (17-22) and their reduction afforded the target oxazolidin-2-one derivatives 23-28. Racemic isocytoxazones 2a and 2b were prepared by an independent route starting from 4-methoxystyrene epoxide. Pure enantiomers of these diastereomeric racemates were separated by HPLC chromatography on chiral stationary phases. Their CD spectra, along with those of previously prepared enantiomers of cis-cytoxazone 1a and trans-cytoxazone 1b are discussed.

    References

  • 1 Kakeya H. Morishita M. Kobinata K. Osono M. Ishizuka M. Osada H. J. Antibiot.  1998,  51:  1126 
  • 2 Kakeya H. Morishita M. Koshino H. Morita T. Kobayashi K. Osada H. J. Org. Chem.  1999,  64:  1052 
  • 3 Hameršak Z. Ljubović E. Merćp M. Mesić M. Šunjić V. Synthesis  2001,  1989 
  • 4 Sakamoto Y. Shiraishi A. Seonhee J. Nakata T. Tetrahedron Lett.  1999,  40:  4203 
  • 5 Miyata O. Asai H. Naito T. Synlett  1999,  1915 
  • 6 Park JN. Ko SY. Koh HY. Tetrahedron Lett.  2000,  41:  5553 
  • 7 Carda M. Gonzales F. Sanchez R. Marco JA. Tetrahedron: Asymmetry  2002,  13:  1005 
  • 8 Marković D. Hameršak Z. Višnjevac A. Kojić -Prodić B. Šunjić V. Helv. Chim. Acta  2000,  83:  603 
  • 9 Nicolaou KC. Boddy CNC. Li H. Koumbis AE. Hughes R. Natarajan S. Jain NF. Ramanjulu JM. Brase S. Solomon ME. Chem.-Eur. J.  1999,  2602 
  • 10 Proni G. Pescitteli G. Huang X. Quraishi NQ. Nakanishi K. Berova N. Chem. Commun.  2002,  1590 
  • 11 Huang X. Fujioka N. Pescitelli G. Koehn FE. Williamson RT. Nakanishi K. Berova N. J. Am. Chem. Soc.  2002,  124:  10320 
  • 12 Organikum   VEB Deutscher Verlag der Wissenschaften; Berlin: 1968.  p.454