Synthesis and evaluation of the trypanocidal and antimicrobial activities of ariltetralin lignan derivatives

Author(s)

Vanessa de Andrade Royo

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC)
• Defense date: 2008-03-24

Examining board members

Jairo Kenupp Bastos; Sergio de Albuquerque; Sérgio Ricardo Ambrosio; Niege Araçari Jacometti Cardoso Furtado; Rosângela Silva

• Advisor: Jairo Kenupp Bastos

Abstract

The (3,4-methylenodioxiphenyl)-3-methoxycarbonyl-3-butenoic acid (3) was obtained in 60 % yield by reacting pyperonal and methyl succinate. Acid 3 was submitted to catalytic reduction furnishing the 4-(3,4-methylenedioxiphenyl)-3- methoxicarbonyl-3-butanoic acid (4), yielding 80 %. Then, compound 4 was reacted with Ca(BH4)2 and H+, furnishing 4-(3,4-methylenedioxiphenyl)-4,5-dihydro-2(3H)-furanone (5), yielding 70 %. Piperonal was added to compound 5 to produce 7-hidroxyhinoquinin (6), yielding 89% of a mixture of diasteroisomers (6a and 6b), which was separate by crystallization. The reaction of both compounds 6a e 6b with CF3CO furnished an aryltetralin lignan derivative poligamain (7), yielding 98 %. Poligamain was reduced by using DIBAL-H in THF, to furnish compound 9. Compound 9, constituted of an enantiomeric mixture was separated by chiral HPLC. All the obtained compounds were analyzed by 1H NMR, BB and DEPT techniques. Regarding the biological assays, the compounds 6, 7 and 9 were assayed against oral pathogens by determining its MIC values. The best results obtained for the (+) 9 isomer was against S. mutans (250 µM), S. salivarius (250 µM), S. sobrinus (280 µM) and S. mitis (280 µM). For the (-) 9 isomer it was active against S. sanguinis (280 µM) while (9) displayed higher activity against L. Casei (370 µM) and E. faecalis (710 µM). Regarding the in vitro trypanocidal assay, on one hand the best result was observed for the mixture of enantiomers (9), which displayed IC50 = 1.4 µM and lysis of 61.9% ± 0.9 at 32 µM. On the other hand, both isolated enantiomers were less active by displaying IC50 of 351.8 µM and 135 µM for (-) 9 and (+) 9, respectively and lysis of 47.3% ± 5.9 at 128 µM, for (+) enantiomer. (AU)