Transformações químicas do (+)-10b,14-diol-allo-aromadendrano, isolado de duguetia glabriuscula r. e. fries (r. e. fries) (annonaceae) e avaliações biológicas de alguns derivados obtidos

Abstract

Recebido em 29/10/96; aceito em 17/4/97 CHEMICAL MODIFICATIONS OF (+)-ALLO-AROMADENDRANE-10β,14-DIOL ISOLATED FROM DUGUETIA GLABRIUSCULA R. E. FRIES (R. E. FRIES) (ANNONACEAE) AND BIO-LOGICAL EVALUATION OF SOME OBTAINED DERIVATIVES. The sesquiterpene (+)-alloaromadendrane-10β-14-diol 1 was the lead compound to the preparation of several derivatives in order to test their biological activity against A. salina, C. sphaerospermum, E. coli and S. aureus. In this way the monoalcohols (+)-viridiflorol 4, 9 and 11 were synthesized from 1 together with the acetal 6, the ketal 7, and the ketone 8. The oxirane 3 and nitrile 5 were also prepared using as an intermediate the tosylate derivative 2.

Complete NMR assignment of (+)‐10β,14‐dihydroxy‐allo‐aromadendrane

“…4) to submit for biological evaluation, 5 and we could compare their 1 H NMR (Table 4) and 13 C NMR spectra (Table 5) with those of the parent in order to support the complete assignments. It is worth mentioning that the hydrogen atoms at C-14 in the 1 H NMR spectra of esters 5 and 6 appear as two singlets (υ D 4.12 and 4.16 ppm, respectively).…”

“…1) has shown antibacterial activity and can be isolated from Pulicaria paludosa 3 and Duguetia glabriuscula. 4 Our group has reported some chemical 5 and microbial 6 transformations of 1 and the evaluation of the biological activity of some derivatives of the compound. 5 Spectral data ( 1 H and 13 C NMR) of 1 have been reported previously, although, regrettably, there was no consensus regarding the labeling of some carbons and protons.…”

“…4 Our group has reported some chemical 5 and microbial 6 transformations of 1 and the evaluation of the biological activity of some derivatives of the compound. 5 Spectral data ( 1 H and 13 C NMR) of 1 have been reported previously, although, regrettably, there was no consensus regarding the labeling of some carbons and protons. 3,4 Accordingly, we were prompted to perform detailed 2D NMR, NMR studies and assign chemical shifts for the structure.…”

Preparation of an Eight-Membered Sesquiterpene Lactone Resulting from Sequential Gif System GoAggIII and MCPBA Oxidation of ( )-10β,14-Dihydroxy-allo-aromadendrane

“…Compound 1 is a natural product isolated from Pulicaria paludosa [ 1 ] and Duguetia glabriuscula [ 2 ]. Investigations concerning chemical modification [ 3 ], microbial transformation [ 4 ], electrolysis [ 5 ] and NMR assignments [ 6 ] of this molecule have demonstrated a great reaction versatility leading to unique carbon frameworks.…”

Estudo fitoquímico das cascas do caule de Duguetia glabriuscula - Annonaceae, biomonitorado pelo ensaio de toxicidade frente a Artemia salina leach

“…Devido a abundância do referido sesquiterpeno, o mesmo foi submetido a algumas modificações na porção funcional da molécula, conduzindo a produtos de baixa atividade antimicrobiana e com atividade frente a Artemia salina, ainda que pouco significativa 7 .…”