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1.
Anim Genet ; 49(3): 265-268, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29570808

RESUMO

Gastrointestinal nematode infection is a constraint on sheep production worldwide. Selective breeding programmes to enhance resistance to nematode infection are currently being implemented in a number of countries. Identification of loci associated with resistance to infection or causative mutations for resistance would enable more effective selection. Loci associated with indicator traits for nematode resistance has been identified in previous studies. In this study, Scottish Blackface, Texel and Suffolk lambs were used to validate the effects at eight genomic regions previously associated with nematode resistance (OAR3, 4, 5, 7, 12, 13, 14, 21). No SNP was significantly associated with nematode resistance at the region-wide level but seven SNPs in three of the regions (OAR4, 12, 14) were nominally associated with trichostrongyle egg count in this study and six of these were also significant when fitted as single SNP effects. Nematodirus egg count was nominally associated with SNPs on OAR3, 4, 7 and 12.


Assuntos
Resistência à Doença/genética , Infecções por Nematoides/veterinária , Doenças dos Ovinos/genética , Carneiro Doméstico/genética , Animais , Cruzamento , Loci Gênicos , Infecções por Nematoides/genética , Contagem de Ovos de Parasitas/veterinária , Polimorfismo de Nucleotídeo Único , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico/parasitologia
2.
N Z Vet J ; 64(3): 174-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26642120

RESUMO

AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement. METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA. RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ∼10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69-70% mapped uniquely to version 3.1 of the ovine genome, and 48-49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study. CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals.


Assuntos
Endoscopia Gastrointestinal/veterinária , Rúmen/patologia , Ovinos , Animais , Biópsia/métodos , Biópsia/veterinária , Endoscopia Gastrointestinal/métodos , Feminino
3.
Parasite Immunol ; 37(12): 605-13, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26480845

RESUMO

Gastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo-dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition, there is growing consumer demand for food products from animals not subjected to chemical treatment. Future mechanisms of nematode control must rely on alternative, sustainable strategies such as vaccination or selective breeding of resistant animals. Such strategies take advantage of the host's natural immune response to nematodes. The ability to resist gastrointestinal nematode infection is considered to be dependent on the development of a protective acquired immune response, although the precise immune mechanisms involved in initiating this process remain to be fully elucidated. In this study, current knowledge on the innate and acquired host immune response to gastrointestinal nematode infection in sheep and the development of immunity is reviewed.


Assuntos
Gastroenteropatias/veterinária , Interações Hospedeiro-Parasita , Nematoides/imunologia , Infecções por Nematoides/veterinária , Doenças dos Ovinos/imunologia , Imunidade Adaptativa , Animais , Anti-Helmínticos/uso terapêutico , Resistência a Medicamentos , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/imunologia , Imunidade Inata , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/imunologia , Ovinos , Doenças dos Ovinos/tratamento farmacológico
4.
Anaesthesia ; 68(12): 1253-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24219251

RESUMO

Double-lumen endobronchial tubes are the most common method of achieving lung isolation and one-lung ventilation during thoracic anaesthesia and surgery. We compared the clinical performance of the Macintosh laryngoscope and the GlideScope(®) during endobronchial intubation with a double-lumen tube. Seventy patients with no predictors for difficult laryngoscopy were allocated randomly to the Macintosh laryngoscope or GlideScope. The time taken for endobronchial intubation with the Macintosh laryngoscope was significantly shorter compared with that taken for the GlideScope, median (IQR [range]) 33 (22-52 [11-438]) s vs 70 (39-129 [21-242]) s, respectively, p = 0.0013. There was no statistical difference in the rate of success at the first attempt (91% vs 83%, respectively). On a numerical rating scale (scored from 0 to 10), the 30 anaesthetists who took part in the study rated endobronchial intubation overall as easier using the Macintosh compared with the GlideScope, 2 (1-3 [0-8]) vs 3 (2-6 [0-10]), respectively, p = 0.003. Postoperative voice changes were also less common in the Macintosh group (8 (22%) vs 17 (58%), p = 0.045). Anaesthetists found the GlideScope more difficult to use than the Macintosh laryngoscope and endobronchial intubation took longer; therefore, we cannot recommend its routine use with double-lumen tubes in patients who are predicted to have a normal airway.


Assuntos
Intubação Intratraqueal/instrumentação , Laringoscópios , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
5.
Clin Transplant ; 26(1): 34-41, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21272072

RESUMO

People with severe cystic fibrosis (CF) lung disease with co-existent CF-associated liver disease (CFLD) are often excluded from consideration of sole lung transplantation, largely because of the concerns that they will subsequently develop hepatic decompensation. This retrospective cohort study aimed at determining whether patients with severe cirrhosis caused by CFLD have any differences in perioperative and relevant post-transplant outcomes compared to CF patients without CFLD when undergoing sole lung transplantation. Six patients with CFLD were matched with 18 CF patients without CFLD undergoing sole lung transplant at the same institution. There were no differences in total operative time or intra-operative requirements for cardiopulmonary bypass or blood products. Over a period of five yr post-transplant, no differences were observed between the two groups in body mass index, six-min walk, lung function, and survival. None of the CFLD subjects developed variceal bleeding; however, one developed hepatocellular and renal failure at four yr post-transplant and is being assessed for liver-kidney transplant. One additional patient with CFLD required repeat lung transplantation for bronchiolitis obliterans syndrome. This study provides evidence that CF patients with liver cirrhosis caused by CFLD can safely be considered for sole lung transplantation provided there is no evidence of significant hepatocellular dysfunction with decompensated cirrhosis or hepatic synthetic failure.


Assuntos
Fibrose Cística/mortalidade , Fibrose Cística/terapia , Cirrose Hepática/mortalidade , Transplante de Pulmão/mortalidade , Adolescente , Adulto , Criança , Fibrose Cística/complicações , Feminino , Volume Expiratório Forçado , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
7.
Soc Cogn Affect Neurosci ; 3(1): 71-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19015097

RESUMO

Extraversion has been shown to positively correlate with activation within the ventral striatum, amygdala and other dopaminergically innervated, reward-sensitive regions. These regions are implicated in emotional responding, in a manner sensitive to attentional focus. However, no study has investigated the interaction among extraversion, emotion and attention. We used fMRI and dynamic, evocative film clips to elicit amusement and sadness in a sample of 28 women. Participants were instructed either to respond naturally (n = 14) or to attend to and continuously rate their emotions (n = 14) while watching the films. Contrary to expectations, striatal response was negatively associated with extraversion during amusement, regardless of attention. A negative association was also observed during sad films, but only when attending to emotion. These findings suggest that attentional focus does not influence the relationship between extraversion and neural response to positive (amusing) stimuli but does impact the response to negative (sad) stimuli.


Assuntos
Tonsila do Cerebelo/fisiologia , Atenção/fisiologia , Gânglios da Base/fisiologia , Mapeamento Encefálico , Extroversão Psicológica , Afeto/fisiologia , Emoções/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Valores de Referência , Adulto Jovem
8.
Br J Nutr ; 100(1): 70-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18081945

RESUMO

Two feeding trials were conducted with pigs to determine the effects of blueberry supplementation on plasma lipid levels and other indices of cardiovascular benefit. In the first trial, where basal diets contained a high level of plant-based components (70 % soya, oats and barley), supplementation with 1, 2 and 4 % blueberries resulted in a decrease in total, LDL- and HDL-cholesterol. The greatest reduction was observed in the 2 % blueberry-fed pigs, where total, LDL- and HDL-cholesterol were reduced 11.7, 15.1 and 8.3 %, respectively. In the second trial where basal diets contained only 20 % (w/w) of soya, oats and barley, the lipid-modulating effect of blueberries was attenuated, so that supplementation with 1.5 % blueberries reduced total cholesterol by 8 %, which occurred only in pigs whose diets had been supplemented with cholesterol (0.08 %), NaCl (0.11 %) and fructose (9 %). In the first feeding trial, blueberry supplementation had no effect on blood platelet activity. Blueberry supplementation also had no effect on the susceptibility of leucocyte DNA to oxidation in the first trial and no effect on the susceptibility of LDL to oxidation in the second trial. Results of these two feeding trials are discussed in relation to the effects of basal diet composition on lipid-modulating effects of blueberries.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Mirtilos Azuis (Planta) , Lipídeos/sangue , Sus scrofa/sangue , Animais , Coagulação Sanguínea/fisiologia , Dieta , Ingestão de Alimentos/fisiologia , Masculino , Ativação Plaquetária/fisiologia , Sus scrofa/crescimento & desenvolvimento , Aumento de Peso/fisiologia
9.
J Food Sci ; 73(6): M292-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19241561

RESUMO

Highbush blueberries, cv 'Burlington', were treated with 22, 45, 50, or 60 degrees C water for 15 or 30 s along with an untreated control. Fruit were then stored for 0, 1, 2, or 4 wk at 0 degrees C and 2 or 9 d at 20 degrees C prior to evaluation of microbial population and fruit quality. After 4 wk of storage, the hot water treatment at 60 degrees C resulted in 92% marketable berries, followed by 90% at 50 degrees C, 88% at 45 degrees C, and 83% at 22 degrees C compared with 76% in untreated controls. Decay incidence was reduced to 0.6%, 1.2%, 1.4%, or 2.8% with 60, 50, 45, or 22 degrees C water treatments, respectively, compared with 5.1% in controls following 4 wk at 0 degrees C and 2 d at 20 degrees C. After an additional 7 d at 20 degrees C, decay in fruit treated at 60 degrees C for 15 or 30 s remained at 1.8% and 0.4%, respectively, compared to 37.4% in controls. Weight loss of berries treated with hot water was 0.4% against 3.8% in controls, and shriveled and split berries were also reduced compared to controls (P<0.001). Aerobic plate count and yeast and mold count were reduced by 0.45 to 0.7 log at 60 degrees C for 30 s. Botrytis cinerea and Colletotrichum sp. were the dominant fungal pathogens causing decay of Burlington blueberries during storage. Hot water treatments also immediately induced an increase in ethanol and reduced fruit titratable acidity and soluble solids content, but had no significant effect on fruit firmness, pH, or most flavor volatile concentrations.


Assuntos
Bactérias/crescimento & desenvolvimento , Mirtilos Azuis (Planta)/microbiologia , Conservação de Alimentos/métodos , Frutas/microbiologia , Frutas/normas , Fungos/crescimento & desenvolvimento , Comportamento do Consumidor , Qualidade de Produtos para o Consumidor , Temperatura Alta , Concentração de Íons de Hidrogênio , Fatores de Tempo , Água
10.
J Appl Microbiol ; 103(6): 2657-63, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17916159

RESUMO

AIMS: To investigate the effects of ozone on inactivation of Listeria innocua on solid media. METHODS AND RESULTS: Suspensions of L. innocua ranging from 4.5 x 10(4 )- 6.4 x 10(4) CFU ml(-1) were inoculated onto potato dextrose agar (PDA, pH 5.6 and 6.8) and nutrient agar (NA, pH 6.0 and 6.8), then exposed to gaseous ozone. Variable factors included postinoculation standing time at 20 degrees C before exposure to ozone, ozone concentration, treatment duration and treatment temperature (5 or 20 degrees C). The interaction among ozone concentration, treatment duration, media and temperature in effecting changes in colony-forming units (CFU) was significant. The 100 nl l(-1) ozone treatment for 2 h reduced the microbial populations by 2-3 log CFU ml(-1). Cell viability decreased more rapidly on PDA than on NA. The average time to obtain a 2 log CFU ml(-1) reduction was 1.3 h at 20 degrees C and 2.5 h at 5 degrees C (P < 0.001). CONCLUSIONS: Gaseous ozone effectively inactivates L. innocua at concentrations of 50 and 100 nl l(-1) during short exposure times at both 5 and 20 degrees C. The Gompretz model can be utilized for determining the response of L. innocua to ozone over time. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides useful information on ozone inactivating Listeria spp., which may be imposed on ensuring quality and safety of horticultural produce and food products.


Assuntos
Desinfetantes/farmacologia , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Listeria/efeitos dos fármacos , Ozônio/farmacologia , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Gases , Listeria/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Temperatura , Fatores de Tempo
11.
J Econ Entomol ; 95(5): 958-65, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12403422

RESUMO

Economic control of Rhagoletis mendax was achieved by applying insecticidal sprays to commercial lowbush blueberry vegetative fields, in a biennial production system, rather than to the fruiting fields, when the threshold was exceeded. The viability of this integrated pest management of R. mendax for lowbush blueberries was demonstrated over a 9-yr interval in New Brunswick where three sites were monitored for 2 yr, eight sites for 4 yr, and one site for 9 yr. Control of R. mendax in lowbush blueberry fields was achieved in 2 yr when the fields were isolated, and in 3 yr when there were adjacent lowbush blueberry fields.


Assuntos
Agricultura/métodos , Ericaceae , Controle de Insetos/métodos , Tephritidae , Animais , Dimetoato , Feminino , Inseticidas , Masculino
12.
Int J Obstet Anesth ; 11(1): 52-6, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15321577

RESUMO

A parturient at 35 weeks' gestation presented with severe shortness of breath, orthopnea and signs of fetal compromise. She was diagnosed with a large mediastinal tumour occupying 65% of transthoracic diameter, and a pericardial effusion. The trachea, both mainstem bronchi, pulmonary artery and superior vena cava were compressed. Her dyspnea continued despite relief of the cardiac tamponade by percutaneous drainage. Tissue obtained via anterior mediastinotomy, performed under local anesthesia infiltration, revealed a definitive diagnosis of non-Hodgkin's lymphoma. The patient improved symptomatically following initiation of steroids and chemotherapy. She was delivered by elective cesarean section under epidural anesthesia on the fifth day after starting chemotherapy. The postoperative course was complicated by the development of a large pleural effusion that required drainage. Mother and baby were well at three and six-month follow up oncology visits.

13.
J Org Chem ; 66(20): 6768-74, 2001 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11578233

RESUMO

The cis-1,2-dihydrocatechol 3, which can be obtained in enantiomerically pure form by microbial dihydroxylation of bromobenzene, has been converted into the enantiomer, ent-1, of the cyclolysine-based marine natural product bengamide E (1).


Assuntos
Antineoplásicos/síntese química , Azepinas/síntese química , Animais , Anti-Helmínticos/síntese química , Antineoplásicos/farmacologia , Azepinas/farmacologia , Catecóis/química , Divisão Celular/efeitos dos fármacos , Endotélio Vascular/citologia , Humanos , Concentração Inibidora 50 , Poríferos/química , Estereoisomerismo , Células Tumorais Cultivadas , Veias Umbilicais
14.
Anesthesiology ; 95(5): 1096-102, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11684977

RESUMO

BACKGROUND: Positive end-expiratory pressure (PEEP) is commonly applied to the ventilated lung to try to improve oxygenation during one-lung ventilation but is an unreliable therapy and occasionally causes arterial oxygen partial pressure (PaO(2)) to decrease further. The current study examined whether the effects of PEEP on oxygenation depend on the static compliance curve of the lung to which it is applied. METHODS: Forty-two adults undergoing thoracic surgery were studied during stable, open-chest, one-lung ventilation. Arterial blood gases were measured during two-lung ventilation and one-lung ventilation before, during, and after the application of 5 cm H(2)O PEEP to the ventilated lung. The plateau end-expiratory pressure and static compliance curve of the ventilated lung were measured with and without applied PEEP, and the lower inflection point was determined from the compliance curve. RESULTS: Mean (+/- SD) PaO(2) values, with a fraction of inspired oxygen of 1.0, were not different during one-lung ventilation before (192 +/- 91 mmHg), during (190 +/- 90), or after ( 205 +/- 79) the addition of 5 cm H(2)O PEEP. The mean plateau end-expiratory pressure increased from 4.2 to 6.8 cm H(2)O with the application of 5 cm H(2)O PEEP and decreased to 4.5 cm H(2)O when 5 cm H(2)O PEEP was removed. Six patients showed a clinically useful (> 20%) increase in PaO(2) with 5 cm H(2)O PEEP, and nine patients had a greater than 20% decrease in PaO(2). The change in PaO(2) with the application of 5 cm H(2)O PEEP correlated in an inverse fashion with the change in the gradient between the end-expiratory pressure and the pressure at the lower inflection point (r = 0.76). The subgroup of patients with a PaO(2) during two-lung ventilation that was less than the mean (365 mmHg) and an end-expiratory pressure during one-lung ventilation without applied PEEP less than the mean were more likely to have an increase in PaO(2) when 5 cm H(2)O PEEP was applied. CONCLUSIONS: The effects of the application of external 5 cm H(2)O PEEP on oxygenation during one-lung ventilation correspond to individual changes in the relation between the plateau end-expiratory pressure and the inflection point of the static compliance curve. When the application of PEEP causes the end-expiratory pressure to increase from a low level toward the inflection point, oxygenation is likely to improve. Conversely, if the addition of PEEP causes an increased inflation of the ventilated lung that raises the equilibrium end-expiratory pressure beyond the inflection point, oxygenation is likely to deteriorate.


Assuntos
Complacência Pulmonar , Respiração com Pressão Positiva , Respiração , Doenças Torácicas/cirurgia , Adulto , Idoso , Feminino , Volume Expiratório Forçado , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Fluxo Expiratório Máximo , Pessoa de Meia-Idade
15.
Anesthesiol Clin North Am ; 19(3): 497-541, vi, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11571904

RESUMO

Surgery of the upper airway requires diagnostic or therapeutic manipulation of the respiratory tree despite ongoing ventilation. Whether internal or external access to the conducting airway is required, anesthesiologist and surgeon, who must work together closely, share the airway. The anesthetic technique is influenced by the chosen mode of ventilation.


Assuntos
Anestesia , Sistema Respiratório/cirurgia , Anestesia/métodos , Broncoscopia , Humanos , Intubação Intratraqueal , Laringoscopia , Terapia a Laser , Complicações Pós-Operatórias , Respiração Artificial/métodos , Traqueia/cirurgia
16.
Clin Diagn Lab Immunol ; 8(4): 690-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11427412

RESUMO

A better understanding of how human immunodeficiency virus (HIV) coinfection affects the course of hepatitis C virus (HCV) infection is required to select patients with HIV who would benefit from current HCV therapy. Between June 1996 and March 2000, HCV RNA levels were quantified for 1,279 patients at the Louisiana State University Health Sciences Center; 28 of these patients were coinfected with HIV. HCV loads were quantified by the Bayer branched-DNA assay with a lower limit of detection of 0.2 Meq/ml. We compared the median HCV RNA levels of for patients coinfected with HIV and HCV and patients infected only with HCV who were in the same age range (23 to 55 years). The median HCV load for the 28 patients coinfected with HCV and HIV (17.8 Meq/ml) was significantly greater (P < 0.05) than that for similarly aged patients infected only with HCV (6.1 Meq/ml). The HCV load did not correlate with age or sex for either group of patients. A significant (R = -0.4; P < 0.05) negative correlation was observed between HCV load and CD4 count in the coinfected group, for whom the CD4 counts at the time of HCV load analysis ranged from 6 to 1,773/mm(3). The increased HCV load in patients coinfected with HCV and HIV compared to that in patients infected only with HCV and the inverse relationship of the HCV load to the CD4 count indicate that immunosuppression results in decreased control of HCV replication. In addition, we report significantly higher HCV loads among coinfected African Americans than Caucasians.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , Hepacivirus/crescimento & desenvolvimento , Hepatite C/virologia , Carga Viral , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Adulto , Fatores Etários , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Contagem de Linfócito CD4 , Feminino , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Fatores Sexuais
17.
J Org Chem ; 66(7): 2382-93, 2001 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-11281779

RESUMO

The total synthesis of the epidermal growth factor inhibitor reveromycin B (2) in 25 linear steps from chiral methylene pyran 13 is described. The key steps involved an inverse electron demand hetero-Diels-Alder reaction between dienophile 13 and diene 12 to construct the 6,6-spiroketal 11 which upon oxidation with dimethyldioxirane and acid catalyzed rearrangement gave the 5,6-spiroketal aldehyde 9. Lithium acetylide addition followed by oxidation/reduction and protective group manipulation provided the reveromycin B spiroketal core 8 which was converted into the reveromycin A (1) derivative 6 in order to confirm the stereochemistry of the spiroketal segment. Introduction of the C1-C10 side chain began with sequential Wittig reactions to form the C8-C9 and C7-C6 bonds, and a tin mediated asymmetric aldol reaction installed the C4 and C5 stereocenters. The final key steps to the target molecule 2 involved a Stille coupling to introduce the C21-C22 bond, succinoylation, selective deprotection, oxidation, and Wittig condensation to form the final C2-C3 bond. Deprotection was effected by TBAF in DMF to afford reveromycin B (2) in 72% yield.


Assuntos
Antibióticos Antineoplásicos/síntese química , Piranos/síntese química , Compostos de Espiro/síntese química , Antibióticos Antineoplásicos/farmacologia , Fator de Crescimento Epidérmico/antagonistas & inibidores , Piranos/farmacologia , Compostos de Espiro/farmacologia , Estereoisomerismo
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