- LTA-mediated synthesis and complete assignment of1H and 13C NMR data of two natural 11-nordrimanes: Isonordrimenone and polygonone
-
Two naturally occurring 11-nordrimanes were synthesized, and their 1H and 13C NMR spectra were unambiguously assigned in full for the first time. Copyright
- Moreno-Osorio, Luis,Espinoza, Luis,Cuellar, Mauricio,Preite, Marcelo
-
-
Read Online
- Comparative study on the larvicidal activity of drimane sesquiterpenes and nordrimane compounds against drosophila melanogaster til-til
-
Natural compounds from Drimys winteri Forst and derivatives exhibited larvicidal effects against Drosophila melanogaster til-til. The most active compound was isodrimenin (4). The highest lethal concentration to the larvae of D. melanogaster was 4.5 ± 0.8 mg/L. At very low concentrations drimenol (1), confertifolin (3), and drimanol (5) displayed antifeedant and larvae growth regulatory activity. The antifeedant results of nordrimanic and drimanic compounds were better in first instar larvae. The EC50 value of polygodial (2) was 60.0 ± 4.2 mg/L; of diol 15 45.0 ± 2.8 mg/L, and of diol 17 36.9 ± 3.7 mg/L, while the new nordrimane compound 12 presented a value of 83.2 ± 3.5 mg/L.
- Montenegro, Ivan,Pino, Luis,Werner, Enrique,Madrid, Alejandro,Espinoza, Luis,Moreno, Luis,Villena, Joan,Cuellar, Mauricio
-
p. 4192 - 4208
(2013/06/26)
-
- Structural requirements for the antifungal activities of natural drimane sesquiterpenes and analogues, supported by conformational and electronic studies
-
Seventeen drimanes including polygodial (1), isopolygodial (2), drimenol (3) and confertifolin (4) obtained from natural sources and the semi-synthetic derivatives 5-17 obtained from 1-3, were evaluated in vitro for antifungal properties against a unique panel of fungi with standardized procedures by using two end-points, MIC100 and MIC50. A SAR analysis of the whole series, supported by conformational and electronic studies, allowed us to show that the Δ7,8 -double bond would be one of the key structural features related to the antifungal activity. The MEPs obtained for active compounds exhibit a clear negative minimum value (deep red zone) in the vicinity of the Δ7,8 -double bond, which is not present in the inactive ones. Apart of this negative zone, a positive region (deep blue) appears in 1, which is not observed either in its epimer 2 nor in the rest of the active compounds. The LogP of active compounds varies between 2.33 and 3.84, but differences in MICs are not correlated with concomitant variations in LogP values.
- Derita, Marcos,Montenegro, Ivan,Garibotto, Francisco,Enriz, Ricardo D.,Fritis, Mauricio Cuellar,Zacchino, Susana A.
-
p. 2029 - 2051
(2013/04/10)
-