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1.
Emerg Infect Dis ; 26(3): 596-600, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32091368

RESUMO

During 2015-2018, seven schools in rural Vietnam experienced diphtheria outbreaks. Multilocus sequence types were the same within schools but differed between schools. Low vaccine coverage and crowded dormitories might have contributed to the outbreaks. Authorities should consider administering routine vaccinations and booster doses for students entering the school system.


Assuntos
Corynebacterium diphtheriae/isolamento & purificação , Difteria/epidemiologia , Surtos de Doenças , Instituições Acadêmicas , Adolescente , Criança , Serviços de Saúde da Criança , Pré-Escolar , Corynebacterium diphtheriae/genética , Demografia , Difteria/etiologia , Difteria/prevenção & controle , Feminino , Humanos , Lactente , Masculino , Tipagem de Sequências Multilocus , Vacinação , Vietnã/epidemiologia , Adulto Jovem
2.
ChemistryOpen ; : e202400139, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171770

RESUMO

Alcohols are common alkylating agents and starting materials alternative to harmful alkyl halides. In this study, a simple, benign and efficient pathway was developed to synthesize 1,3-diphenylpropan-1-ols via the ß-alkylation of 1-phenylethanol with benzyl alcohols. Unlike conventional borrowing hydrogen processes in which alcohols were activated by transition-metal catalyzed dehydrogenation, in this work, t-BuONa was suggested to be a dual-role reagent, namely, both base and radical initiator, for the radical coupling of aromatic alcohols. The cross-coupling reaction readily proceeded under transition metal-free conditions and an inert atmosphere, affording 1,3-diphenylpropan-1-ol with an excellent yield. A good functional group tolerance in benzyl alcohols was observed, leading to the production of various phenyl-substituted propan-1-ol derivatives in moderate-to-good yields. The mechanistic studies proposed that the reaction could involve the formation of reactive radical anions by base-mediated deprotonation and single electron transfer.

3.
RSC Adv ; 12(54): 34831-34836, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36540248

RESUMO

Methods for direct functionalization of C(sp2)-H bonds in pyrrolo[1,2-a]quinoxalines have witnessed emerging development over the last decade. Herein we report a new tactic to afford a selective sulfenylation of 4-aryl pyrrolo[1,2-a]quinoxalines with diaryl disulfides. The reactions proceeded in the presence of a copper catalyst and potassium iodide promoter. Functionalities including nitro, ester, amide, methylthio, and halogen groups were all tolerated. Our method offers a convenient route to obtain highly substituted pyrrolo[1,2-a]quinoxalines-based thioethers in moderate to good yields.

4.
RSC Adv ; 11(10): 5451-5455, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35423092

RESUMO

We report a method for addition of α-bromophenylacetic acids to vinyl C[double bond, length as m-dash]C bonds in styrenes to afford γ-lactones. Reactions employed a simple cobalt catalyst Co(NO3)2·6H2O in the presence of dipivaloylmethane (dpm) ligand. Many functionalities including halogen, ester, and nitro groups were compatible with reaction conditions. If α-bromoesters were used, vinylacetates were the major products.

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