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1.
Article in English | MEDLINE | ID: mdl-38409719

ABSTRACT

BACKGROUND: As a malignant tumor, osteosarcoma (OS) ranks first place among adolescent cancers and is susceptible to developing resistance to chemotherapeutic agents. Differently, traditional Chinese medicine (TCM) has multiple pharmacodynamic targets and complex biological components, which can inhibit tumor survival and drug resistance and gradually play an important role in the treatment of sarcoma. METHODS: This study is to systematically evaluate the safety and efficacy of TCM combined with chemotherapy performed in the clinical treatment of OS. Based on multiple mainstream databases, eleven articles on the relationship between natural products and chemotherapy involving 656 patients were selected from all the literature published as of June 2022. Revman 5.4 software was used for a comprehensive search analysis, supplemented by established exclusion criteria, the Jadad scale, and the evaluation methods provided by Cochrane. RESULTS: The efficiency of TCM combined with chemotherapy was significantly increased compared with chemical drugs alone [OR=2.56, 95% CI (1.36,4.79), Z=2.92, P=0.003]. Meanwhile, the adverse reactions such as nausea and vomiting, hepatotoxicity, and hematological changes caused by chemical drugs were alleviated correspondingly. CONCLUSION: This study indicates that the mode of TCM combined with chemotherapy sheds light on the clinical treatment of OS, which is much better than the one-way mode.

2.
Org Lett ; 25(32): 5984-5988, 2023 Aug 18.
Article in English | MEDLINE | ID: mdl-37548642

ABSTRACT

A novel oxidative cleavage and fluoromethylthiolation reaction of C═C bonds has been developed that represents the first and general method for the preparation of mono-, di-, and trifluoromethylthioesters from alkenes. The protocol features excellent product selectivity and substrate suitability. Various observations suggested that the protocol proceeded via a two-step radical process and that aldehyde was the key intermediate. What's more meaningful is that this route provides a new direction for converting alkenes into higher-value-added carbonyl-containing chemicals.

3.
J Org Chem ; 87(10): 6573-6587, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35522737

ABSTRACT

A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in functional materials and medicinal chemistry, this approach would find broad applications.


Subject(s)
Esters , Hydrazines , Esters/chemistry , Free Radicals , Hydrazines/chemistry
4.
Chemistry ; 28(39): e202200981, 2022 Jul 11.
Article in English | MEDLINE | ID: mdl-35487846

ABSTRACT

A new class of electrophilic monofluoromethylselenolation reagents, Se-(fluoromethyl) benzenesulfonoselenoates, has been developed. They can be readily prepared from sodium benzenesulfinates, Se powder and ClCFH2 in one step under mild reaction conditions. Se-(fluoromethyl) benzenesulfonoselenoates are efficient electrophilic monofluoromethylselenolation reagents for a wide range of nucleophiles including indole, 6-azaindole, pyrrole, thiophene, electron-rich arene, aryl boronic acid and alkyne. The monofluoromethylselenolation approach features mild and environmentally friendly reaction conditions, good tolerance of various functional groups, and broad substrate scope.


Subject(s)
Alkynes , Boronic Acids , Electrons , Indicators and Reagents
5.
J Org Chem ; 86(19): 13618-13630, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34498883

ABSTRACT

Reported herein is an intramolecular dehydrogenative coupling of two inert aryl C-H bonds for the synthesis of aporphine analogues. The process represents a novel tool for the preparation of aporphines via palladiun-catalyzed C-H bond activation. The present reaction is compatible with various functional groups, and the coupling products have been further applied for the synthesis of natural products aporphine and zenkerine.


Subject(s)
Aporphines , Palladium , Catalysis
6.
Org Biomol Chem ; 19(21): 4752-4759, 2021 06 02.
Article in English | MEDLINE | ID: mdl-33978053

ABSTRACT

A novel photocatalyzed cross-dehydrogenative coupling reaction of N-Boc-tetrahydroisoquinolines with α,ß-unsaturated ketones has been developed. This research provides an easy access to a variety of C1-substituted tetrahydroisoquinolines, which can be further transformed into benzo[a]-quinolizine-2-ones, the skeletons of natural products with a wide range of biological activities. The load of the photocatalyst is low and the oxidant is inexpensive and less toxic.

7.
Org Lett ; 23(4): 1216-1221, 2021 02 19.
Article in English | MEDLINE | ID: mdl-33528267

ABSTRACT

An efficient and unprecedented strategy for the synthesis of 1,4-enediones from saturated ketones has been developed via palladium-catalyzed oxidative dehydrogenation. The protocol employs molecular oxygen as the sole oxidant and represents an atom- and step-economic process. The approach showed broad substrate scope, good functional group tolerance, and complete E-stereoselectivity. The reaction mechanism has been investigated through deuterium-labeling experiments and intermediate experiments.

8.
Org Lett ; 23(5): 1921-1927, 2021 03 05.
Article in English | MEDLINE | ID: mdl-33606544

ABSTRACT

A direct and efficient palladium-catalyzed oxidative dehydrogenative fluoroalkoxylation of benzaldehydes is reported here for the first time. The method features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. The protocol employs the transient directing group strategy, thereby avoiding the additional installation and removal of directing groups, endowing the method with great advantages of atom and step economy. The approach should find broad applications in drug synthesis and discovery processes.

9.
Int J Pharm ; 580: 119123, 2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32035258

ABSTRACT

The development of small molecule anticancer drugs, with low water solubility and high toxicity, into polymeric prodrugs has developed into a promising strategy in clinical application. In this study, we synthesized a novel G3-C12-mediated esterase-sensitive tumor-targeting polymeric prodrug of camptothecin (CPT), P(OEGMA-co-CPT-co-G3-C12), and explored its anticancer activity against androgen-independent prostate cancer in vitro and in vivo. Compared to free CPT, the multifunctional polymeric prodrug demonstrated improved water solubility and stability, higher intracellular uptake, and enhanced cytotoxicity in DU145 cells in vitro. Furthermore, it displayed an improved accumulation in the tumor and an enhanced anticancer activity in vivo. Hence, P(OEGMA-co-CPT-co-G3-C12) could be a promising drug in the treatment of androgen-independent prostate cancer.


Subject(s)
Blood Proteins/metabolism , Camptothecin/metabolism , Drug Delivery Systems/methods , Drug Development/methods , Galectins/metabolism , Prodrugs/metabolism , Prostatic Neoplasms, Castration-Resistant/metabolism , Animals , Camptothecin/administration & dosage , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/physiology , Cell Survival/drug effects , Cell Survival/physiology , Dose-Response Relationship, Drug , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Polymers/administration & dosage , Polymers/metabolism , Prodrugs/administration & dosage , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/pathology , Xenograft Model Antitumor Assays/methods
10.
Org Lett ; 21(8): 2731-2735, 2019 04 19.
Article in English | MEDLINE | ID: mdl-30916984

ABSTRACT

An unprecedented cross-dehydrogenative-coupling (CDC) reaction of saturated aldehyde ß-C-H with arenes to form cinnamaldehydes via the cleavages of four C-H bonds has been developed. The reaction possesses complete E-stereoselectivity for the C═C double bond. The protocol is featured by atom and step economy, mild reaction conditions, and convenient operation.

11.
Org Lett ; 20(7): 1794-1797, 2018 04 06.
Article in English | MEDLINE | ID: mdl-29522346

ABSTRACT

The utilization of the transient directing strategy into the direct oxidative dehydrogenative arylation of aldehydes with arenes was reported for the first time. Featured by mild reaction conditions, good functional group compatibility, and great regioselectivity, the method should find broad applications in new medicine and material development and discovery processes.

12.
Org Lett ; 20(7): 1910-1913, 2018 04 06.
Article in English | MEDLINE | ID: mdl-29522348

ABSTRACT

A new chemistry of azo compounds that is a radical generation and addition in situ of azocarboxylic tert-butyl esters to synthesize hydrazines has been described. The protocol provides a novel strategy for the synthesis of various hydrazines. The advantages of the transformation include broad substrate scope, benign conditions, and convenient operation.

13.
Nat Prod Bioprospect ; 8(1): 1-21, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29340966

ABSTRACT

Endocannabinoid system is related with various physiological and cognitive processes including fertility, pregnancy, during pre- and postnatal development, pain-sensation, mood, appetite, and memory. In the latest decades, an important milestone concerning the endocannabinoid system was the discovery of the existence of the cannabinoid receptors CB1 and CB2. Anandamide was the first reported endogenous metabolite, which adjusted the release of some neurotransmitters through binding to the CB1 or CB2 receptors. Then a series of cannabinomimetric lipids were extracted from marine organisms, which possessed similar structure with anandamide. This review will provide a short account about cannabinomimetric lipids for their extraction and synthesis.

14.
Angew Chem Int Ed Engl ; 57(6): 1663-1667, 2018 02 05.
Article in English | MEDLINE | ID: mdl-29271048

ABSTRACT

Difluoromethylthioester compounds are yet another important kind of organofluorine compound and are reported here for the first time. They can be efficiently synthesized from various aldehydes. The synthetic method features mild reaction conditions, good tolerance of functional groups, broad substrate scope, and importantly, no metal is involved in the reaction. The approach has the potential to become an important tool for the late-stage functionalization of advanced synthetic intermediates, and should have many applications in medicinal chemistry.

15.
Org Lett ; 19(13): 3516-3519, 2017 07 07.
Article in English | MEDLINE | ID: mdl-28598164

ABSTRACT

A palladium-catalyzed asymmetric allyl-allyl cross-coupling reaction to construct the chiral quaternary carbon center of crinane alkaloids has been developed. On the basis of an efficient approach, the enantioselective synthesis of (-)-crinane (1) is presented, and the first asymmetric total synthesis of (+)-4a-dehydroxycrinamabine (2) was achieved by subsequent oxidation, 1,4-conjugate addition, RCM reaction, reductive amination, and Pictet-Spengler reaction. The method provided an alternative strategy for the syntheses of crinane alkaloids and other Amaryllidaceae natural products.

16.
Org Lett ; 19(4): 798-801, 2017 02 17.
Article in English | MEDLINE | ID: mdl-28145725

ABSTRACT

The palladium-catalyzed intramolecular C-H/C-H coupling reaction of two simple arenes to generate 6H-benzo[c]chromenes has been reported for the first time. The approach features broad substrate scope and good tolerance of functional groups and uses molecular oxygen as the terminal oxidant. The high efficiency of the approach is verified by concise total synthesis of natural product cannabinol.

17.
Chem Asian J ; 12(1): 130-144, 2017 Jan 03.
Article in English | MEDLINE | ID: mdl-27860323

ABSTRACT

An efficient palladium(II)-catalyzed intermolecular direct ortho-alkenylation and acetoxylation of phenols has been developed. The reaction proceeded via a seven-membered cyclopalladated intermediate and showed complete regio- and diastereoselectivity. The approach also provided an efficient route for the synthesis of coumarins and benzofurans.


Subject(s)
Benzofurans/chemical synthesis , Coumarins/chemical synthesis , Palladium/chemistry , Phenols/chemistry , Pyridines/chemistry , Benzofurans/chemistry , Catalysis , Coumarins/chemistry , Molecular Structure , Stereoisomerism
18.
Chemistry ; 21(32): 11335-9, 2015 Aug 03.
Article in English | MEDLINE | ID: mdl-26094845

ABSTRACT

Silver-catalyzed coupling of two C sp(3)-H groups to form 1,4-diketones have been developed for the first time. The resultant ketones then undergo cyclization to synthesize tetrasubstituted furans, thiophenes, and pyrroles from benzyl ketone derivatives in a one-pot reaction process. This highly-efficient synthetic method, which utilizes air as the terminal oxidant and readily accessible starting materials, displays a wide substrate scope and broad functional-group tolerance.

19.
Org Lett ; 17(7): 1692-5, 2015 Apr 03.
Article in English | MEDLINE | ID: mdl-25764041

ABSTRACT

A new chemistry of hydrazines that is a copper-catalyzed radical reaction to synthesize vinyl sulfones from readily available N-tosylhydrazones has been described. The protocol provides a novel strategy for the synthesis of various vinyl sulfones including α, ß-disubstituted ones and terminal ones. The advantages of the transformation include excellent E stereoselectivity, broad substrate scope, low cost of reagents, and convenient operation. A novel and efficient one-pot synthesis of alkynes from N-tosylhydrazones has been achieved. The studies provide important complementary approaches for the syntheses of vinyl sulfones and alkynes.

20.
Org Lett ; 16(10): 2732-5, 2014 May 16.
Article in English | MEDLINE | ID: mdl-24805285

ABSTRACT

A general and efficient palladium-catalyzed intermolecular direct C-H homocoupling of furans and thiophenes has been developed. The reaction is characterized by using molecular oxygen as the sole oxidant and complete C5-position regioselectivity. Both C2- and C3-substituted furans or thiophenes are appropriate substrates. The approach provides a straightforward, facile, and economical route to bifurans and bithiophenes under mild reaction conditions.


Subject(s)
Furans/chemistry , Heterocyclic Compounds, 2-Ring/chemical synthesis , Oxidants/chemistry , Oxygen/chemistry , Palladium/chemistry , Thiophenes/chemistry , Catalysis , Combinatorial Chemistry Techniques , Furans/chemical synthesis , Heterocyclic Compounds, 2-Ring/chemistry , Molecular Structure , Thiophenes/chemical synthesis
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