New PKS-NRPS tetramic acids and pyridinone from an Australian marine-derived fungus, Chaunopycnis sp.

Author(s)

Shang, Zhuo ^[1] ; Li, Li ^{[2, 3]} ; Esposito, Breno P. ^[4] ; Salim, Angela A. ^[1] ; Khalil, Zeinab G. ^[1] ; Quezada, Michelle ^[1] ; Bernhardt, Paul V. ^[5] ; Capon, Robert J. ^[1]

Affiliation

^[1] Univ Queensland, Inst Mol Biosci, Brisbane, Qld 4072 - Australia

^[2] Chinese Acad Med Sci, Inst Mat Med, Beijing Key Lab Act Subst Discovery & Druggabil E, Beijing 100050 - Peoples R China

^[3] Peking Union Med Coll, Beijing 100050 - Peoples R China

^[4] Univ Sao Paulo, Inst Chem, BR-05508000 Sao Paulo - Brazil

^[5] Univ Queensland, Sch Chem & Mol Biosci, Brisbane, Qld 4072 - Australia

• Document type: Journal article
• Source: ORGANIC & BIOMOLECULAR CHEMISTRY; v. 13, n. 28, p. 7795-7802, 2015.
• Web of Science Citations: 14

Abstract

Chemical analysis of a marine-derived fungus, Chaunopycnis sp. (CMB-MF028), isolated from the inner tissue of a pulmonate false limpet Siphonaria sp., collected from rock surfaces in the intertidal zone of Moora Park, Shorncliffe, Queensland, yielded the tetramic acid F-14329 (1) and new analogues, chaunolidines A-C (2-4), together with the new pyridinone chaunolidone A (5), and pyridoxatin (6). Structures inclusive of absolute configurations were assigned to 1-6 on the basis of detailed spectroscopic analysis, X-ray crystallography, electronic circular dichroism (ECD), biosynthetic considerations and chemical inter-conversion. Chaunolidine C (4) exhibits modest Gram-positive antibacterial activity (IC50 5-10 mu M), while chaunolidone A (5) is a selective and potent inhibitor (IC50 0.09 mu M) of human non-small cell lung carcinoma cells (NCI-H460). Tetramic acids 1-4 form metal chelates with Fe(III), Al(III), Cu(II), Mg(II) and Zn(II). (AU)

• FAPESP's process: 13/13166-4 - Bioprospection of marine siderophores aiming to iron overload chelation therapy
• Grantee: Breno Pannia Esposito
• Support Opportunities: Scholarships abroad - Research