RESUMO
The first complete synthesis of laetevirenol A was performed in nine steps via intramolecular Friedel-Crafts alkylation in a trans-selective manner. The key phenanthrene intermediate was synthesized by a one-pot Suzuki-Miyaura coupling and an aldol condensation cascade reaction.
Assuntos
Fenantrenos/química , Fenantrenos/síntese química , Alquilação , Catálise , Estrutura Molecular , EstereoisomerismoRESUMO
Highly stereoselective, palladium-catalyzed α-arylation reactions of 3-aryl-1-indanones with aryl bromides are described. The use of sodium tert-butoxide as a base in this process is required to elevate the efficiencies and stereoselectivities of these reactions. The new methodology was successfully applied to a highly efficient route for the asymmetric synthesis of (+)-pauciflorol F.
Assuntos
Hidrocarbonetos Bromados/química , Indanos/química , Paládio/química , Estilbenos/síntese química , Catálise , Estrutura Molecular , Estereoisomerismo , Estilbenos/químicaRESUMO
A common strategy for the synthesis of a 7-membered-ring system with a Suzuki-Miyaura coupling followed by an acid/base-promoted intramolecular aldol condensation reaction has been developed. The reaction of 2'-bromoacetophenones with 2-formylphenylboronic acids in the presence of Pd(OAc)(2) and CataCXium PIntB L8 efficiently provided biaryl compounds, which were transformed to a wide array of dibenzo[a,c]cyclohepten-5-ones in excellent yields by a sequential treatment with p-TsOH, followed by 10% aq NaOH.
Assuntos
Aldeídos/química , Cicloeptanos/síntese química , Catálise , Cicloeptanos/química , LigantesRESUMO
A series of natural aristolactams and their analogues have been prepared and evaluated for antitumor activity against human cancer cells, including multi-drug resistant cell lines. Naturally occurring aristolactams, such as aristolactam BII (cepharanone B), aristolactam BIII, aristolactam FI (piperolactam A), N-methyl piperolactam A, and sauristolactam showed moderate antitumor activities in selected cell lines. However, several synthetic aristolactam derivatives exhibited potent antitumor activities against a broad array of cancer cell lines with GI(50) values in the submicromolar range.
Assuntos
Antineoplásicos/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Lactamas/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Aporfinas/síntese química , Aporfinas/química , Aporfinas/toxicidade , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/toxicidade , Humanos , Lactamas/química , Lactamas/toxicidadeRESUMO
A general synthesis of dibenzoxepine lactams has been developed using a one-pot Cu-catalyzed etherification/aldol condensation cascade reaction. The reaction of 4-hydroxyisoindolin-1-one with a wide range of 2-bromobenzaldehydes in the presence of a copper catalyst provided various aristoyagonine derivatives in good yields.
Assuntos
Benzoxepinas/síntese química , Cobre/química , Isoquinolinas/síntese química , Lactamas/síntese química , Aldeídos/química , Benzaldeídos/química , Benzoxepinas/química , Catálise , Isoquinolinas/química , Lactamas/química , Estrutura Molecular , EstereoisomerismoRESUMO
A one-pot transition-metal-free, base-mediated synthesis of dibenzo[b,f]oxepins was developed. The reaction of 2-halobenzaldehydes with (2-hydroxyphenyl)acetonitriles proceeds via a sequential aldol condensation and intramolecular ether formation reaction in the presence of Cs(2)CO(3) and molecular sieves in toluene.