Planta Med 2003; 69(5): 481-483
DOI: 10.1055/s-2003-39696
Letter
© Georg Thieme Verlag Stuttgart · New York

Absolute Configuration of Keisslone, a New Antimicrobial Metabolite from Keissleriella sp. YS4108, a Marine Filamentous Fungus

C. H. Liu1 , J. Y. Liu1 , L. L. Huang1 , W. X. Zou1 , R. X. Tan1
  • 1Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, P. R. China
Further Information

Publication History

Received: September 4, 2002

Accepted: December 7, 2002

Publication Date:
12 June 2003 (online)

Abstract

In order to purify enough material for establishing the absolute stereochemistry of the new antifungal metabolite 3,6,8-trihydroxy-3-[3,5-dimethyl-2-oxo-3(E)-heptenyl]-2,3-dihydronaphthalen-1(4H)-one produced by Keissleriella sp., a marine filamentous fungus (strain number: YS 4108) [1], a repeated growth and fractionation of the fungal culture was performed to give instead a new antimicrobial metabolite, keisslone (1), the structure of which was elucidated on the basis of spectral analyses including homo- and hetero-nuclear correlation NMR experiments (HMQC, COSY, NOESY and HMBC). The absolute configuration of metabolite 1 was determined mainly by its CD data and NOESY spectrum. The compound 1 was shown to be inhibitory against the human pathogenic fungi Candida albicans, Trichophyton rubrum and Aspergillus niger with MICs of 50, 70, 40 μg/mL, respectively.

Abstract

In order to purify enough material for establishing the absolute stereochemistry of the new antifungal metabolite 3,6,8-trihydroxy-3-[3,5-dimethyl-2-oxo-3(E)-heptenyl]-2,3-dihydronaphthalen-1(4H)-one produced by Keissleriella sp., a marine filamentous fungus (strain number: YS 4108) [1], a repeated growth and fractionation of the fungal culture was performed to give instead a new antimicrobial metabolite, keisslone (1), the structure of which was elucidated on the basis of spectral analyses including homo- and hetero-nuclear correlation NMR experiments (HMQC, COSY, NOESY and HMBC). The absolute configuration of metabolite 1 was determined mainly by its CD data and NOESY spectrum. The compound 1 was shown to be inhibitory against the human pathogenic fungi Candida albicans, Trichophyton rubrum and Aspergillus niger with MICs of 50, 70, 40 μg/mL, respectively.

References

  • 1 Liu C H, Meng J C, Zou W X, Huang L L, Tang H Q, Tan R X. Antifungal metabolite with a new carbon skeleton from Keissleriella sp. YS4108, a marine filamentous fungus.  Planta Medica. 2002;  68 363-5
  • 2 Fenical W. Chemical studies of marine bacteria: developing a new resource.  Chem Rev. 1993;  93 1673-83
  • 3 Faulkner D J. Marine natural products.  Nat. Prod. Rep.. 2001;  18 1-49
  • 4 Yajima A, Mori K. Absolute configuration of phytocassanes as proposed on the basis of the CD spectrum of synthetic (+)-2-deoxyphytocassane A.  Tetrahedron Lett. 2000;  41 351-4
  • 5 Liu J Y, Liu C H, Zou W X, Tian X, Tan R X. Leptosphaerone, a metabolite with a novel skeleton from Leptosphaeria sp. IV403, an endophytic fungus in Artemisia annua .  Helv Chim Acta. 2002;  85 2664-7
  • 6  F,  D,  A W,  L F,  F,  M G,  G. In vitro activities of the new antifungal triazole SCH 56 592 against common and emerging yeast pathogens.  Antimicrob Agents Chemother. 2000;  44 226-9

Prof. Dr. Ren Xiang Tan

Institute of Functional Biomolecules

Nanjing University

Nanjing 21093

P. R. China

Email: rxtan@netra.nju.edu.cn

Phone: +86-25-3592945

Fax: +86-25-3302728