Abstract
1011
Spirolaxine is an interesting secondary metabolite, containing a 3-methoxy-5-hydroxy-phthalide nucleus linked through a five-member methylene chain to a spiroketal group, that we have previously isolated from MPGA cultures of Sporotrichum laxum (Basidiomycetae) in poor yield.1 The structure was elucidated by means of NMR and chemical evidence but the stereochemistry was unknown. Now this fungal strain has been grown on ground rice medium (80%, plus agar 20%) into Roux flasks and the EtOAc extract was first purified through a flash silica gel column, followed by preparative RP-HPLC. The configurations of the four stereogenic centers have been determined as 7R, 6′R, 10′R and 13′R (or vice versa).2 Biological evaluation of spirolaxine activity was performed in vitro on endothelial cells and a variety of tumor cell lines.3 It was demonstrated that at not toxic doses (1-0.1 μM) spirolaxine determined an almost complete inhibition of bovine microvascular endotehalial cell (BMEC) chemotaxis and differentiation on Matrigel. In addition, after 24-48 h of treatment with doses ranging from 1 to 40 μM the molecule determined a dose-dependent inhibition of proliferation of different cells including endothelial cells (BMEC and HUVEC) and tumor cell lines (LoVo, HL60). In conclusion, spirolaxine demonstrated interesting properties to be further investigated in angiogenesis and tumor models. 1 A.Arnone, G.Assante, G.Nasini, O.Vajna de Pava, Phytochemistry 1990, 613 2 G.Candiani, L.Malpezzi, G.Nasini, G.Giannini 23rd IUPAC International Symp. on the Chemistry of Nat. Prod. Florence 28 july-2 august 2002 3 Patent WO01/68070 G.Penco, C.Pisano, G.Giannini
- American Association for Cancer Research
Volume 64, Issue 7 Supplement
