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1.
J Org Chem ; 88(11): 6682-6690, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37184949

RESUMEN

A novel three-component reaction has been established that allows a flexible and practical approach to pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine derivatives from phenylglyoxal, ß-ketoamide, and 5-aminopyrazole with acetic acid as the solvent. Various dihydropyrazolo[3,4-b]pyrrolo[3,4-d]pyridin-6(3H)-one were isolated in moderate to good yields with broad functional group tolerance.

2.
Front Psychiatry ; 13: 819075, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295782

RESUMEN

Methamphetamine use is a serious problem in China. Compulsory isolation detoxification is the main treatment measure for drug dependents, whereas psychological interventions in compulsory isolation detoxification centers are extremely inadequate. The current study aimed to examine the effects of mindfulness-based relapse prevention (MBRP) on methamphetamine dependence patients in Chinese compulsory isolation detoxification treatment institutions. Forty-one methamphetamine dependent patients received 16-sessions of MBRP in 8 weeks and assessments were conducted at the baseline, 4-, 8-week (after the whole intervention). Results of repeated measured ANOVAs showed there was no significant effect on emotions and cravings. Findings indicated that the effects of MBRP are still difficult to make firm conclusions due to the insignificant results. Future studies should modify the MBRP and ensure that it is suitable for compulsory isolation detoxification treatment institutions in China.

3.
J Org Chem ; 87(5): 3546-3554, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35170321

RESUMEN

Visible-light-induced, iridium catalyzed, para-selective C-H difluoroalkylation of aniline derivatives under mild reaction conditions is reported. Various substrates and bioactive compounds, such as precursors of vorinostat and chlorpropham, were all well tolerated. This protocol features a wide substrate scope, high regioselectivity, low catalyst usage, and operational simplicity.

4.
J Org Chem ; 86(12): 8226-8235, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34080879

RESUMEN

Iodine(III)-mediated synthesis of 4-iodo-N-phenylaniline from iodobenzene has been achieved, and the reaction can proceed under mild conditions. A variety of functional groups were well tolerated, providing the corresponding products in moderate to good yields. The remaining iodine group provides an effective platform for converting the products into several valuable asymmetric diphenylamines. Most importantly, this reaction can be easily scaled up to the ten-gram scale, highlighting its synthetic utility. The mechanistic study revealed that the in situ generated aryl hypervalent iodine intermediate is the key factor to realize this para-selective C-H amination reaction.

5.
Angew Chem Int Ed Engl ; 60(35): 19030-19034, 2021 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-34160867

RESUMEN

The direct incorporation of a trifluoromethyl group on an aromatic ring using a radical pathway has been extensively investigated. However, the direct highly para-selective C-H trifluoromethylation of a class of arenes has not been achieved. In this study, we report a light-promoted 4,5-dichlorofluorescein (DCFS)-enabled para-selective C-H trifluoromethylation of arylcarbamates using Langlois reagent. The preliminary mechanistic study revealed that the activated organic photocatalyst coordinated with the arylcarbamate led to para-selective C-H trifluoromethylation. Ten-gram scale reaction performs well highlighting the synthetic importance of this new protocol.

6.
Org Lett ; 23(11): 4209-4213, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-33999646

RESUMEN

A novel approach to synthesize 3-methylisoquinolines via a one-pot, two-step, palladium(II)-catalyzed tandem C-H allylation/intermolecular amination and aromatization is reported. A wide series of 3-methylisoquinoline derivatives were obtained directly using this method in moderate to good yields, and we highlight the synthetic importance of this new transformation.

7.
Harm Reduct J ; 16(1): 34, 2019 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-31133016

RESUMEN

BACKGROUND: This study was to characterize the Methadone Maintenance Treatment (MMT) in Shanghai, China, and to explore factors associated with the decline of patients in MMT during 2005-2016. METHODS: Both qualitative and quantitative methods were used in this study. Based on the data from Shanghai Centers for Disease Control (CDC), we described the changes in the number of patients who received MMT, and new enrollment each year from 2005 to 2016. Focus groups were conducted with 22 patients, and in-depth interviews were conducted with 9 service providers. RESULTS: Quantitative data demonstrate that the number of new enrollment began to decline in 2009, and the number of patients receiving MMT began to decline in 2012. The main reasons for dropout include (1) discontinuing medication due to unknown reasons (25%), (2) criminal activities other than drug-related crimes (20%), (3) relapse to heroin use (16%), and (4) physical disease (10%). Qualitative assessment results indicate that the major reasons for the decline of patients in MMT are as follows: (1) the increase of Amphetamine-type stimulants (ATS) use in recent years, (2) limited knowledge about MMT in both patients and MMT staff, (3) complicated enrollment criteria, and (4) discrimination against drug use. CONCLUSION: Various reasons to explain the decline of patients in MMT in Shanghai, China, were identified. Government agencies, service providers, and other stakeholders need to work together and overcome identified barriers to support MMT programs in China.


Asunto(s)
Trastornos Relacionados con Anfetaminas/epidemiología , Analgésicos Opioides/uso terapéutico , Dependencia de Heroína/tratamiento farmacológico , Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos/tendencias , Adolescente , Adulto , Anciano , China/epidemiología , Femenino , Grupos Focales , Infecciones por VIH , Conocimientos, Actitudes y Práctica en Salud , Dependencia de Heroína/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Pacientes Desistentes del Tratamiento , Investigación Cualitativa , Recurrencia , Adulto Joven
8.
Org Lett ; 21(2): 365-368, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30618258

RESUMEN

A rhodium(III)-catalyzed intermolecular C-H amination of ketoxime and iodobenzene diacetate-enabled N-N bond formation in the synthesis of indazoles has been developed. A variety of functional groups were well tolerated, providing the corresponding products in moderate to good yields. Moreover, the nitro-substituted ketoximes are well compatible in this reaction, leading to the corresponding products in moderate to good yields.

9.
Org Lett ; 20(8): 2454-2458, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29634278

RESUMEN

A convenient and practical approach to synthesize ortho-alkynylated arylalkylamines through ortho-selective C-H functionalization has been developed using Cbz-amide as the directing group and Ir(III) as the catalyst. Various substrates were well tolerated, affording the corresponding products in moderate to good yields. Moreover, preliminary mechanistic study revealed the role of the amide as the coordination center to cooperate with the Ir(III) complex during C-H activation. Development of this Cbz-amide-promoted CAr-H functionalization offers a practical approach with potential applications in organic synthesis.

10.
ACS Comb Sci ; 19(11): 708-713, 2017 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-28985045

RESUMEN

A microwave-assisted regioselective synthesis of 3-functionalized indole derivatives via a three-component domino reaction of anilines, arylglyoxal monohydrates, and cyclic 1,3-dicarbonyl compounds is described. The main advantages of this protocol are short reaction times, practical simplicity, its metal-free nature, the availability of starting materials, green solvents, and high regioselectivity.


Asunto(s)
Indoles/síntesis química , Microondas , Compuestos de Anilina/química , Técnicas de Química Sintética , Técnicas Químicas Combinatorias , Glioxal/química
11.
Org Biomol Chem ; 15(37): 7909-7916, 2017 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-28895604

RESUMEN

A concise and efficient approach to design and synthesize hetero[5]helicene-like molecules and coumarin derivatives is reported. Intriguingly, using the same catalyst (silica sulfuric acid), and a different solvent and reaction temperature, the reaction selectively afforded hetero[5]helicene-like molecules 3 or coumarin derivatives 4. Product 4 has a highly planar geometry, and product 3 can be regarded as hetero[5]helicene-like because of its helical conformation.


Asunto(s)
Cumarinas/síntesis química , Microondas , Compuestos Policíclicos/síntesis química , Cumarinas/química , Estructura Molecular , Compuestos Policíclicos/química
12.
Org Biomol Chem ; 15(24): 5112-5116, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28589976

RESUMEN

With the assistance of the same bidentate directing group, the first example of sequential, controllable C-H functionalization of ß-arylethylamines at different positions for the construction of polysubstituted arenes is reported. Pd-Catalyzed highly regioselective ortho-C-H functionalization reactions of meta-aryl substituted arylethylamines are performed, including alkynylation, iodination, acetoxylation and amination, which led to a concise approach to the synthesis of polysubstituted ß-arylethylamine derivatives.

13.
J Org Chem ; 82(13): 6831-6839, 2017 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-28617597

RESUMEN

An efficient synthesis of isoindolin-1-ones from oxalyl amide-protected benzylamines, through ruthenium-catalyzed intramolecular C(sp2)-H carbonylation, has been developed. Variously substituted benzylamines could be well tolerated in this new protocol, affording the corresponding products in moderate to excellent yields. This approach constitutes the first example of Ru(II)-catalyzed C(sp2)-H carbonylation with isocyanate as a novel commercially available carbonyl source.

14.
Mol Divers ; 21(2): 293-304, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28144767

RESUMEN

A concise, efficient one-pot synthesis of functionalized chromeno[4,3-b]pyridine derivatives via a three-component reaction of 4-oxo-4H-chromene-3-carbaldehydes, malononitrile or cyanoacetates, and aromatic amines under catalyst-free conditions in an environmentally friendly medium (ethanol-water, 3:1 v/v) is described. This synthesis involves a group-assisted purification process, which avoids traditional recrystallization and chromatographic purification methods.


Asunto(s)
Piridinas/química , Piridinas/síntesis química , Técnicas de Química Sintética , Etanol/química , Tecnología Química Verde , Agua/química
15.
Org Lett ; 18(23): 5998-6001, 2016 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-27934363

RESUMEN

The first example of oxidative C-H/C-H cross-coupling of oxalyl amide-protected benzylamines and various heteroarenes in the presence of a rhodium(III) catalyst has been developed. The route provides a means of synthesizing ortho-heteroarylated benzylamines. The methodology presents broad substrate scope, great functional group tolerance, and good to excellent yields in the synthesis of substituted benzylamines. The study also reveals that the thienoisoquinoline derivatives can be accessed through the intramolecular amination of thiophenyl-substituted benzylamines with palladium(II).

16.
J Org Chem ; 81(13): 5681-9, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27286881

RESUMEN

Pd-catalyzed regioselective coupling of γ-C(sp(3))-H bonds of oxalyl amide-protected amino acids with heteroaryl and aryl iodides is reported. A wide variety of iodides are tolerated, giving the corresponding products in moderate to good yields. Various oxalyl amide-protected amino acids were compatible in this C-H transformation, thus representing a practical method for constructing non-natural amino acid derivatives.

17.
Chem Commun (Camb) ; 52(42): 6903-6, 2016 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-27142086

RESUMEN

The first bidentate directing group assisted highly selective meta arylation of ß-arylethylamine derivatives via palladium/norbornene catalysis is reported, and the range of aryl iodides for the oxalyl amide assisted meta-selective arylation reactions is broadest yet reported. This meta arylation also proceeds well with thiophene derivatives, giving the corresponding products in satisfactory yields. And three-step functionalization of arylethyloxalamide with three different functional groups is successfully performed.

18.
J Org Chem ; 80(18): 9297-306, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26309049

RESUMEN

A method for palladium-catalyzed oxalyl amide-directed arylation of α-unsubstituted aliphatic amines with aryl iodides has been developed. A wide variety of aryl iodides are tolerated in this transformation, affording various γ-arylpropylamine derivatives. Heterocyclic iodides can also be competent reagents in this γ-C(sp(3))-H bonds transformation.

19.
J Org Chem ; 80(16): 7896-904, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26197216

RESUMEN

A highly regioselective palladium-catalyzed ester-directed ortho-olefination of phenyl acetic and propionic esters with olefins via C-H bond activation has been developed. A wide variety of phenyl acetic and propionic esters were tolerated in this transformation, affording the corresponding olefinated aromatic compounds. The ortho-olefination of heterocyclic acetic and propionic esters also took place smoothly giving the products in good yields, thus proving the potential utility of this protocol in synthetic chemistry.


Asunto(s)
Alquenos/síntesis química , Ésteres/química , Compuestos Organometálicos/química , Paladio/química , Alquenos/química , Catálisis , Estructura Molecular
20.
J Org Chem ; 80(16): 8435-42, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26193420

RESUMEN

A simple and efficient one-pot construction of pyrazolo[3,4-e]indolizine derivatives via a diethylamine-catalyzed three-component domino reaction of arylglyoxals, cyclic 1,3-diones, and 5-aminopyrazoles under microwave irradiation is described. In this one-pot transformation, seven bonds and two new rings are efficiently formed. This synthesis was confirmed to follow the group-assisted-purification (GAP) chemistry process, which can avoid traditional recrystallization or chromatography purification methods.


Asunto(s)
Dietilaminas/química , Indolizinas/síntesis química , Pirazoles/síntesis química , Catálisis , Ciclización , Indolizinas/química , Microondas , Estructura Molecular , Pirazoles/química
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