Diterpenoids from Azorella compacta

Absolute Configuration of Mulinolic Acid

“…The spectroscopic data showed resemblance with those similar mulinane structures reported in the literature [4][5][6][7][8][9][10][11] . The relative stereochemistry of mulinolic acid was assigned based on careful analysis of the ROESY experiment 6 , and in this work we have assigned the absolute configuration of this diterpene using X-ray crystal analysis. Data collection, structural determination and refinement was performed with a Bruker AXS D8-Venture, Triumph-μI-Cu with graphite-monochromated CuKα radiation (1.54178 Å).…”

“…The collected fractions (80) were combined according to TLC analysis (Kieselgel F254 plates, developed with Hexane: EtOAc 8:2 v/v, and spots visualized by spraying with vanillin: sulfuric acid 2 % in ethanol and heating) and fifteen combined fractions were obtained. Fraction 5 (350 mg) was re-chromatographed using the same chromatographic system and the known compounds: mulin-11,13-dien-20-oic acid 6 (120 mg) and mulinolic acid 7 (60 mg). Recrystallization de mulinolic acid from ethyl acetate a room temperature yielded white crystals, which were suitable for X-ray diffraction analysis.…”

Mulinane-type diterpenoids from Azorella compacta display antiplasmodial activity

“…The 1 H and 13 C NMR spectra of 1, together with analysis of 1 H COSY, HMQC and HMBC experiments, revealed the presence of an isopropyl group [d C 31.3 (CH), 22.6 (CH 3 ) and 23.5 (CH 3 ); d H 1.46 overlapped signal, 0.81 d and 1.02 d (J ¼ 6:4 Hz in both signals)]. The similarities observed in the 13 C NMR and 1 H NMR spectra of 1 and mulin-11,12-dien-20-oic acid (Loyola et al, 1997b), were indicative of the presence of a mulinane diterpenoid moiety in 1. We assumed, by analogy with other mulinane diterpenoids (Loyola et al, 1990(Loyola et al, , 1997a(Loyola et al, ,b, 1998a) that the substituents at C-3, C-5 and C-8 were b orientated as well as the proton at C-9.…”

Microbial transformation of the diterpene mulin‐11,13‐dien‐20‐oic acid by Mucor plumbeus

“…The other known signals were deduced by comparison with the spectra of compound 1. [5] Compound 3 was obtained as yellow oil. Analysis of the 1 Hand 13 C-NMR spectra (Table 1) 3H, s, H-17) that confirmed its mulinane structure.…”

“…[1 -4] Mulin-11,13-dien-20-oic acid is the major diterpene isolated from Azorella compacta. [5] It has been shown to display trichomonicidal effects and to have trypanocidal activity too. [4,6] Microbial transformation is now becoming a useful tool for structural modifications of bioactive natural products and to allow the production of regio-and stereoselective compounds under mild conditions, especially the inactived sites of hydrocarbons.…”