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1.
Beilstein J Org Chem ; 9: 2570-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367421

RESUMO

2-Chloro-3-amino-4-picoline (CAPIC) is a strategic building block for the preparation of nevirapine, a widely-prescribed non-nucleosidic reverse transcriptase inhibitor for the treatment of HIV-infected patients. A continuous synthesis to the bromo derivative of a CAPIC intermediate, 2-bromo-4-methylnicotinonitrile, that terminates in a dead-end crystallization is described. The route uses inexpensive, acyclic commodity-based raw materials and has the potential to enable lower cost production of nevirapine as well as other value added structures that contain complex pyridines. The route terminates in a batch crystallization yielding high purity CAPIC. This outcome is expected to facilitate regulatory implementation of the overall process.

2.
Org Lett ; 15(20): 5298-301, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24093933

RESUMO

Pyridines with 2,3,4 and/or 5 substitution remain challenging to prepare. Existing strategies to form multisubstituted 2-halonicotinonitriles via enamines suffer from dimerization of the starting alkylidene malononitriles resulting in low yields. Through alteration of reaction conditions, a new high yielding method into enamines was realized by condensing DMF-DMA and alkylidene malononitriles in the presence of substoichiometric acetic anhydride. Cyclization of the resulting enamines under Pinner conditions provided 2-halonicotinonitriles in high overall yields.


Assuntos
Alcenos/química , Ácidos Nicotínicos/síntese química , Nitrilas/química , Nitrilas/síntese química , Estrutura Molecular , Ácidos Nicotínicos/química
3.
Arch Surg ; 137(8): 960-5; discussion 965-6, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12146999

RESUMO

BACKGROUND: The stage-stratified survival following gastrectomy for gastric cancer is far better in Japan than in the United States. The process of carcinogenesis may differ in gastric cancers from Japan and the United States, accounting for prognostic differences, as patients of Asian descent treated in United States also exhibit superior survival in comparison with non-Asian patients. HYPOTHESIS: The phenotype of gastric cancer differs between Japanese and American patients. DESIGN: Retrospective case-case (blinded) study. SETTING: University hospitals in Japan and the United States. PATIENTS AND METHODS: We compared the frequency of microsatellite instability (MSI) at 7 loci from formalin-fixed paraffin-embedded gastrectomy specimens, between cases of gastric cancer at Hitachi General Hospital (N = 18) and in US patients of European descent treated in Orange County, Calif (N = 20). Microsatellite instability, Lauren classification, and T stage were determined without knowledge of the country of origin of the specimens. MAIN OUTCOME MEASURE: The frequency of MSI in Japanese vs European American gastric cancer specimens. RESULTS: The frequency of MSI in Japanese gastric carcinoma specimens was higher than in specimens from American patients of European descent (39% vs 20%, respectively). In contrast, a high frequency of MSI was demonstrated in only 3 European American specimens (15% of all specimens in this group). Tumors from Japanese and American men were more likely to demonstrate MSI than those from women (50% vs 5.6%, respectively; P =.004). Among advanced-stage tumors, Japanese specimens were significantly more likely to demonstrate MSI (55%) than European American specimens (7.1%; P =.02). Specimens from Japan and America demonstrating MSI were equally likely to be from men, involve the gastroesophageal junction, and demonstrate intestinal histologic abnormalities. CONCLUSIONS: Advanced gastric cancers from Japan are more likely to demonstrate MSI. These data warrant a study of larger numbers of patients to assess whether differences in MSI expression correlates with prognostic differences between gastric carcinoma in patients in Japan vs the United States.


Assuntos
Repetições de Microssatélites/genética , Neoplasias Gástricas/genética , Idoso , Europa (Continente)/etnologia , Feminino , Humanos , Japão , Masculino , Estados Unidos
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