Owing to their challenging structures and promising biological profiles,spirooxindole alkaloids have long attracted much attention from the synthetic community.Herein,we wish to describe a concise,protecting-group-fre...Owing to their challenging structures and promising biological profiles,spirooxindole alkaloids have long attracted much attention from the synthetic community.Herein,we wish to describe a concise,protecting-group-free total synthesis of cabucine oxindole A,a putative natural spirooxindole alkaloid and a possible biosynthetic congener of cabucine and palmirine.Key transformations of our approach include a one-step,organocatalytic and enantioselective construction of the spiro[pyrrolidine-3,3'-oxindole]moiety and a Korte rearrangement to furnish the final dihydropyran motif.Biological investigation of 1 and its synthetic intermediates revealed lactone 2 as a mild MOLT-4 and MCF7 cell line inhibitor.展开更多
Main observation and conclusion A full account of the total synthesis of(-)-pallambins A-D(1-6)is described.The strategy was devised by simulating their biosynthetic pathway.The left-part bicyclo[3.2.1]octane system o...Main observation and conclusion A full account of the total synthesis of(-)-pallambins A-D(1-6)is described.The strategy was devised by simulating their biosynthetic pathway.The left-part bicyclo[3.2.1]octane system of pallambins C and D was efficiently constructed via a palladium-catalyzed oxidative cyclization.展开更多
We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivi...We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivity.Computational studies support outer-sphere X–H⋅⋅⋅O_(boryl) hydrogen bond interactions,which are strengthened by bidentate C^C ligand introduction.The method shows broad substrate scope and high functional group tolerance.展开更多
A protecting-group-free enantioselective tandem allylic substitution of o-phenylenediamines and o-aminophenols is realized for the first time with a Pd-WingPhos catalyst,providing expedient access to a series of chira...A protecting-group-free enantioselective tandem allylic substitution of o-phenylenediamines and o-aminophenols is realized for the first time with a Pd-WingPhos catalyst,providing expedient access to a series of chiral vinylsubstituted heterocycles in excellent ee and yields under mild reaction conditions.The protocol is applied successfully to the synthesis of a cholesteryl ester transfer protein(CETP)inhibitor.展开更多
We report the concise and protecting-group-free enantioselective total syntheses of circumdatins F and H.In view of the extreme importance of analogs of quinazolinone alkaloids in drug research and discovery,four anal...We report the concise and protecting-group-free enantioselective total syntheses of circumdatins F and H.In view of the extreme importance of analogs of quinazolinone alkaloids in drug research and discovery,four analogs of bioactive quinazolinobenzodiazepine alkaloids,including demethoxycircumdatin H(12)and N-demethyl-benzomalvin A(13),have been synthesized.The method is based on the low-valent titanium-promoted intra-molecular reductive coupling of imides with o-nitrobenzimides,which yielded quinazolino[3,2-a][1,4]benzodi-azepines under mild conditions.In addition,heptacyclic dehydraasperlicin E(16)has been synthesized from asper-licin C by a NCS-mediated dehydra-cyclization reaction.展开更多
基金Financial support from SZSTI(Nos.JCY120170817110515599,KQTD20150717103157174)the National Natural Science Founda tion of China(Nos.21772082 and 21971104)+3 种基金the Guangdong Innovative Program(No.2019BT02Y335)the Guangdong Provin cial Key Laboratory of Catalysis(No.2020B121201002)the Shen zhen Key Laboratory of Small Molecule Drug Discovery and Syn thesis(No.ZDSY520190902093215877)the Shenzhen Nobel Prize Scientists Laboratory Project(C17783101)is greatly appreci-ated.The authors are grateful to Prof.Qing Ye(SUSTech)for assis-tance with XRD analysis.
文摘Owing to their challenging structures and promising biological profiles,spirooxindole alkaloids have long attracted much attention from the synthetic community.Herein,we wish to describe a concise,protecting-group-free total synthesis of cabucine oxindole A,a putative natural spirooxindole alkaloid and a possible biosynthetic congener of cabucine and palmirine.Key transformations of our approach include a one-step,organocatalytic and enantioselective construction of the spiro[pyrrolidine-3,3'-oxindole]moiety and a Korte rearrangement to furnish the final dihydropyran motif.Biological investigation of 1 and its synthetic intermediates revealed lactone 2 as a mild MOLT-4 and MCF7 cell line inhibitor.
基金This research was supported by the National Natural Science Foundation of China(Nos.21925101 and 21572008).
文摘Main observation and conclusion A full account of the total synthesis of(-)-pallambins A-D(1-6)is described.The strategy was devised by simulating their biosynthetic pathway.The left-part bicyclo[3.2.1]octane system of pallambins C and D was efficiently constructed via a palladium-catalyzed oxidative cyclization.
基金This work was supported by the National Natural Science Foundation of China(Nos.22171284 and 21602249)the Fundamental Research Funds for the Central Universities,the Research Funds of Renmin University of China(No.20XNLG20)the Public Computing Cloud Platform,Renmin University of China.
文摘We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivity.Computational studies support outer-sphere X–H⋅⋅⋅O_(boryl) hydrogen bond interactions,which are strengthened by bidentate C^C ligand introduction.The method shows broad substrate scope and high functional group tolerance.
基金Financial support is provided by the National Natural Science Foundation of China(Nos.82188101,21725205,21432007,21572246,21702223)the Key-Area Research and Development Program of Guangdong Province(No.2020B010188003).
文摘A protecting-group-free enantioselective tandem allylic substitution of o-phenylenediamines and o-aminophenols is realized for the first time with a Pd-WingPhos catalyst,providing expedient access to a series of chiral vinylsubstituted heterocycles in excellent ee and yields under mild reaction conditions.The protocol is applied successfully to the synthesis of a cholesteryl ester transfer protein(CETP)inhibitor.
基金support from the National Natural Science Foundation of China(Nos.21332007 and 21472153)the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)of Ministry of Education.
文摘We report the concise and protecting-group-free enantioselective total syntheses of circumdatins F and H.In view of the extreme importance of analogs of quinazolinone alkaloids in drug research and discovery,four analogs of bioactive quinazolinobenzodiazepine alkaloids,including demethoxycircumdatin H(12)and N-demethyl-benzomalvin A(13),have been synthesized.The method is based on the low-valent titanium-promoted intra-molecular reductive coupling of imides with o-nitrobenzimides,which yielded quinazolino[3,2-a][1,4]benzodi-azepines under mild conditions.In addition,heptacyclic dehydraasperlicin E(16)has been synthesized from asper-licin C by a NCS-mediated dehydra-cyclization reaction.
