A total synthesis of (+)-eremantholide A

One-step biomimetic conversion of a furanoheliangolide into an eremantholide using Stryker’s reagent

“…[1][2][3][4][5] The biological activity of some eremantholides, which includes trypanocidal, 6 antibacterial, 7 anti-inflammatory 8,9 and anti-tumor properties, 10 has prompted several research groups to propose syntheses, both total and partial, for these compounds. [11][12][13][14][15][16][17][18] Nevertheless, most efforts in these synthetic works are directed toward the obtention of eremantholide A (1) and just a few were undertaken toward other eremantholide structures or some generic part of eremantholides structures.…”

Electrophile-Directed Diastereoselective Alkylation of Prochiral Enediolates

“…This represents a rare example of the diastereoselective alkylation of a prochiral enolate directed by a β-stereogenic center in a primary alkyl electrophile. To our knowledge, the only previous examples of this phenomenon are the pioneering studies on the alkylation of 3-substituted oxindole enolates by Overman 6 and of metalated hydroxyfurans by Tadano and Hale . We therefore undertook further studies based on our preliminary observation to better define the scope and generality of the transformation.…”

“…While progress has been made in the catalytic asymmetric alkylation of the more acidic ketone enolates, work in the carboxyl series is still limited to substrates bearing additional acidifying substituents . An alternative but little used strategy is to exploit chirality in the electrophile to control the facial selectivity of attack on a prochiral enolate. − We report herein a new approach to the construction of quaternary α-hydroxy carboxylic derivatives utilizing such a strategy.…”

Estudos conformacionais de lactonas sesquiterpênicas e compostos relacionados

“…Estes compostos possuem uma ponte constituída por um átomo de oxigênio ligando os carbono C 3 e C 10 . 27 Dentre as propriedades biológicas encontradas para os furanoeliangolidos, podemos destacar as atividades esquistomicida, 28 anti-bacteriana, 29 tripanomicida, 30 fungicida, 31 moluscicida, 32 citotóxica, 29 anti-tumoral, 33 analgésica 34 e antiinflamatória. 35 Os furanoeliangolidos com atividade anti-inflamatória mais potente são os da classe a que pertence o goyazensolido (9, R=MeAcr), mostrado na Figura 8.…”