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1.
Chem Asian J ; 18(18): e202300526, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37530657

RESUMO

A facile enantioselective alkynylation of cyclic ketimines attached to a neutral functional group utilizing the dual Cu(I)-CPA catalysis is described. The strategy of the alkynylation of 2-aryl-3H-indol-3-one directly to chiral propargylic amines containing indolin-3-one moiety in good yields and enantioselectivities. Moreover, gram-scale synthesis of chiral propargylamines based C2-quaternary indolin-3-ones was performed. The synthetic applications were confirmed by transformations of the products with no decrease in the yield and enantioselectivity.

2.
Org Biomol Chem ; 21(21): 4393-4397, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37161837

RESUMO

The ß-C-H functionalization of amines is one of the most powerful tools for the synthesis of saturated nitrogen-containing heterocycles in organic synthesis. However, the ß-C-H functionalization of amines via redox-neutral addition with cyclic-ketimines is still unprecedented. Herein, the ß-C-H functionalization of tertiary amines is described, providing the corresponding 1,3-diamines containing the indolin-3-one moiety in high yields via the B(C6F5)3-catalyzed borrowing hydrogen strategy. According to the experimental results, a possible catalytic cycle has been proposed to rationalize the process of this reaction. Notably, the ß-C-H alkylation of amines is external oxidant- and transition-metal-free, which makes a significant contribution to promoting economical chemical synthesis.

3.
J Org Chem ; 88(11): 6599-6610, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37157120

RESUMO

The enantioselective aza-MBH reaction is an efficient strategy for constructing novel carbon-carbon bonds, providing access to multitudinous chiral densely functionalized MBH products. However, the enantioselective aza-MBH reaction of cyclic-ketimines that would generate a versatile synthon is still missing and challenging. Herein, we developed a challenging direct organocatalytic asymmetric aza-MBH reaction involving cyclic ketimines attached to a neutral functional group. Moreover, the α,ß-unsaturated γ-butyrolactam was utilized as a rare nucleophile alkene in this work. The reactions provide enantiomerically enriched 2-alkenyl-2-phenyl-1,2-dihydro-3H-indol-3-ones, bearing with a tetra-substituted stereogenic center. Moreover, this reaction features high α-selectivities, high enantioselectivities (up to 99% ee), and good yields (up to 80%).

4.
Chemistry ; 29(20): e202203914, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36600107

RESUMO

A chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of 5-aminopyrazole derivatives with cyclic ketimines attached to a neutral functional group is reported. This protocol allows the formation of pyrazole-based C2-quaternary indolin-3-ones with high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis of the 5-aminopyrazole-based C2-quaternary indolin-3-ones was performed, with no decrease in the yield and enantioselectivity.

5.
Org Biomol Chem ; 21(3): 489-493, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36541043

RESUMO

The enantioselective aza-Friedel-Crafts reaction is one of the most straightforward and efficient strategies for constructing a new carbon-carbon bond bearing quaternary stereocenter in organic synthesis, but the catalytic asymmetric aza-Friedel-Crafts reaction of naphthols/phenols with cyclic-ketimines attached to a neutral functional group remains still relatively unexplored. Herein, a highly enantioselective aza-Friedel-Crafts reaction of cyclic-ketimines and naphthols/phenols has been realized using a chiral phosphoric acid catalyst. A variety of chiral aminonaphthols (chiral indolin-3-ones) containing a quaternary stereocenter at the C2 position were obtained with excellent outcomes (up to 97% yield, 98% ee). Moreover, the synthetic utility of the enantiomerically enriched chiral aminonaphthols was demonstrated in some efficient transformations. According to the experimental results, a possible transition state model has been proposed to rationalize the origin of asymmetric induction.


Assuntos
Naftóis , Fenóis , Naftóis/química , Fenóis/química , Elétrons , Estereoisomerismo , Estrutura Molecular , Catálise
6.
Medicine (Baltimore) ; 99(7): e18332, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049776

RESUMO

BACKGROUND: Patients with advanced gastric or gastro-oesophageal junction cancer (GC/GEJC) that fail to respond to prior chemotherapy have poor clinical prognosis. Lately, many trials have paid much attention on the oncological outcomes of immune checkpoint inhibitors (ICI). A new therapy based on programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors has recognized as promising prospects for advanced GC/GEJC. We assessed efficacy and safety of PD-L1 antibody versus chemotherapy alone in previously treated non-small cell lung cancer. METHODS: Computerized literature search was done on the published trials in: Pubmed, Embase, Cochrane library updated on June 2019. Randomized controlled trials were selected investigating chemotherapy plus PD-1/PD-L1 versus chemotherapy alone. RESULTS: Three randomized controlled trails were included. The pooled analysis of overall survival (OS) was longer with anti-PD1/PD-L1 than with chemotherapy alone in the OS (OR = 0.66, 95%CI = 0.47-0.92, P = .02) and sub-group OS of GEJC (OR = 0.73, 95%CI = 0.58-0.93, P = .01). Whereas, there is no significant difference in progression-free survival (OR = 0.93, 95%CI = 0.62-1.39, P = .72). The pooling adverse events (AE) data did not achieve advantage in the PD-1/PD-L1 targeted agents (OR = 0.53, 95%CI = 0.13-2.10, P = .36), the same as the treatment-related AE of grade 3 to 5 (OR = 0.53, 95%CI = 0.16-1.74, P = .30). CONCLUSIONS: Treatment of patients with advanced GC/GEJC with PD-1/PD-L1 targeted did result in an improvement in some but not all survival endpoints. Moreover, it had a comparable toxicity profile as compared with chemotherapy alone. More well designed studies are needed to develop a database of all anti-PD1/PD-L1 sub-groups and their individual impact on the differing anti-PD1/PD-L1 treatments.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Junção Esofagogástrica/patologia , Neoplasias Gástricas/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Antígeno B7-H1/antagonistas & inibidores , Humanos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Resultado do Tratamento
7.
Zhong Xi Yi Jie He Xue Bao ; 6(10): 1040-4, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18847539

RESUMO

OBJECTIVE: To study the role of estrogen receptor (ER) and progesterone receptor (PR) in the formation of cholesterol calculus and investigate the effects of Shengqing Capsule (SQC), a Chinese patent herbal medicine with the function of soothing liver and draining gallbladder, on ER and PR expressions. METHODS: A total of 80 female guinea pigs were divided into normal control group, untreated group, ursodeoxycholic acid group (UDCA group) and SQC group. The cholesterol gallstone was induced by feeding the guinea pigs with high-fat lithogenic diet. SQC and UDCA were separately administered to the guinea pigs in the SQC group and UDCA group. After 7-week administration, all the animals were sacrificed to calculate the incidence of calculus formation and detect the expressions the ER and PR in the epithelial tissue of gallbladder by immunohistochemical method. RESULTS: Gallstone was cholesterol calculus detected by infrared spectrum. The incidence of calculus formation in the SQC group (27.78%) was significantly lower than that in the untreated group (81.25%) (X(2)=9.721 5, P=0.001 8). On the basis of Reiner standard, the expression distribution of ER and PR increased gradually from the normal control group through the SQC group and UDCA group to the untreated group. Except for the former two groups and the latter two groups, the differences between the other groups and UDCA group were statistically significant (P<0.05). Besides, the differences of positive expression rates between groups were statistically significant (P<0.05). CONCLUSION: Increased expressions of ER and PR are closely related to the formation of cholesterol stone. And Shengqing Capsule can down-regulate the expressions of ER and PR.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Vesícula Biliar/metabolismo , Cálculos Biliares/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Animais , Cápsulas , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Epitélio/metabolismo , Feminino , Cálculos Biliares/prevenção & controle , Cobaias , Fitoterapia , Distribuição Aleatória
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