Aldol Reaction
Mostrando 13-24 de 39 artigos, teses e dissertações.
-
13. Sintese da macrolactona da migrastatina e analogo : sinteses e aplicações de novos substratos em reações de RCAM catalisadas por [Mo] / Synthesis of the macrolactone of migrastatin and analog : syntheses of new substrates for applications in Mo-catalyzed RCAM
Chapter 1 describes the syntheses of macrolactones 11 and 62a. Macrolactone 11 presents the best tumor cell migration inhibitory effect among the compounds of the migrastatin family synthesized so far. Macrolactone 62a, not described in the literature, is the C8-epimer of macrolactone 62b, which was synthesized by Professor Danishefskys group in 2004 and s
Publicado em: 2009
-
14. Estudos metodológicos visando a síntese da biotina a partir da hidantoína
Biotin (1), a member of the vitamin B complex group, has been an attractive synthetic target due to its biological activity and its applications in different fields such as immunology, radiotherapy and bioanalytical chemistry. In this thesis we report some experimental results for an alternative biotin synthesis, using hydantoin (146) as starting material. T
Publicado em: 2008
-
15. Síntese e avaliação das atividades fitotóxicas e citotóxicas de compostos análogos aos nostoclídeos
The nostoclides are produced by a cyanobacterium Nostoc sp. symbiont of Peltigera canina, and belong to a family of compounds know as -alkylidenebutenolides. Nostoclides have been shown to have moderate cytotoxicity against the mouse neuroblastoma cell lines Neuro-2a CCL and KB CCL 17. Due to the fact that Peltigera canina cultures are usually not contaminat
Publicado em: 2008
-
16. Assinalação Estereoquímica de Produtos e Descrição de Mecanismos para Reações de Acoplamento entre α,α- Diclorocetonas e Compostos Carbonílicos Promovidas por Brometo de Índio(I) / Indium(I) Bromide-Mediated Coupling of α,α-Dichloroketones with Carbonyl Compounds: Stereochemical Assignments and Description of Reaction Mechanisms
This work describes our results on the use of indium(I) bromide in Organic Synthesis, namely the reaction mechanisms and stereochemical outcome. Indium enolates, generated from the reaction between indium(I) bromide and α,α-dichloroketones, react with carbonyl compounds. The primary coupling with aldehydes leads to the diastereoselective synthesis
Publicado em: 2007
-
17. Investigation of a New Synthetic Route to (R)-Baclofen / Estudo de uma nova rota sintética para o fármaco (R)-baclofen
In this work, the feasibility of a new synthetic route to Baclofen was investigated. The starting material, a cis-aziridine, was prepared by ring closure of (2S,3R)-(4-clorophenyl)- serine, under phase transfer conditions (PTC). As for the preparation of the required ß- hydroxy-α-aminoacid, two alternative synthetic strategies were investigated. (i) th
Publicado em: 2007
-
18. Addition of Chiral Allyltrichlorostannanes to Chiral Aldehydes : total syntheseis of (+)-Prelactone B / Adição de aliltriclorestanana quirais a aldeidos quirais : sintese total da (+)-prelactona B
The Lewis-acid mediated reaction of allylsilanes and allylstannanes with aldehydes is a well-known procedure for the preparation of homoallylic alcohols. Chiral allyltrichlorostannanes react with chiral a-methyl, b-alkoxy and syn and anti a-methyl-b-alkoxy aldehydes to give the corresponding homoallylic alcohols with moderate to high 1,4-syn-diastereoselecti
Publicado em: 2006
-
19. Synthesis of the C1-C13 fragment of migrastatin / Sintese do fragmento C1-C13 da migrastatina
Migrastatin was isolated from a cultured broth of Streptomyces sp. MK929-43F1 in 2000 by Imoto and co-workers, as well as from a cultured broth of Streptomyces platensis NRRL 18993 by researchers from Kosan Biosciences. Migrastatin has a remarkable inhibitory effect on the migration of human tumor cells, very important to the tumor metastasis treatment. Its
Publicado em: 2005
-
20. Studies towards a new approach to total synthesis of the (+)-napalilactone, a halogenated sesquiterpene isolated frm marine source / Estudos visando a uma nova abordagem para a sintese total da (+)-Napalilactona, um sesquiterpeno halogenado isolado de fonte marinha
Napalilactona e Patilactona A são dois sesquiterpenóides espirolactônicos isolados de fontes marinhas. Esses sesquiterpenos, biogeneticamente derivados de um esqueleto carbônico do tipo aristoleno, apresentam em suas estruturas quatro centros estereogênicos contínuos e diferem apenas na substituição do heteroátomo (Cl versus OH) vizinho à unidade e
Publicado em: 2005
-
21. Reações aldólicas assimétricas catalíticas
This review describes the use of catalytic asymmetric aldol reactions of silyl enol ethers and silyl (thio)ketene acetals with aldehydes (the Mukaiyama aldol reaction) in order to illustrate its synthetic utility. A variety of Lewis acid and basic reagents were employed for catalytic aldol reactions with high diastereo- and enantioselectivities. The origins
Química Nova. Publicado em: 2003-08
-
22. Sintese total e elucidação estrutural da delactomicina
The natural polyketide delactonmycin isolated from Streptomyces strains displays potent inhibitory activity of the nucleo-cytoplasmic translocation of the HIV -1 regulatory protein Rev. The planar structure of delactonmycin was established by spectroscopic methods, but its relative as well as its absolute configuration remained unknown. In this work, we desc
Publicado em: 2003
-
23. Efeito da substituição por átomos de flúor no equilíbrio conformacional de chalcona
Chalcone (1) and its fluorinated derivatives 2-4, as well as their cyclic analogues 5-10, were synthesized through an aldol condensation reaction between the corresponding ketone and aldehyde. These compounds were characterized by IR, EIMS and ¹H and 13C NMR spectral data. Modern NMR techniques allowed us to conclude that the compounds obtained show E confi
Química Nova. Publicado em: 2001-10
-
24. Studies on the synthesis of heliangolides throught the Diels-Alder reaction. / Estudos sobre a síntese de heliangolidos pela reação de Diels-Alder.
O objetivo deste trabalho foi desenvolver métodos para sintetizar o esqueleto carbônico básico de furanoeliangolidos. Goiazensolido é um típico exemplo destes produtos naturais, cujo núcleo estrutural podemos considerar como sendo de um biciclo[6.2.1]undecano. Imaginamos que este tipo de estrutura poderia ser preparado através da reação de Diels-Ald
Publicado em: 2001