Objective To study the chemical constituents from the aerial parts of Hypericum beani/. Methods Various chromatographic techniques were used to separate the constituents and their structures were elucidated on the bas...Objective To study the chemical constituents from the aerial parts of Hypericum beani/. Methods Various chromatographic techniques were used to separate the constituents and their structures were elucidated on the basis of extensive spectroscopic interpretation. Results Fifteen compounds were isolated from the aerial parts of H. beanii. Their structures were identified as hyperbeanol E （1）, （E）-Iinalool-l-oic acid （2）, （4S,5R）-5-（4＇-methyl-3＇-pentenyl）-4-hydroxy-5-methyl- dihydrofuran-2-one （3）, benzoic acid （4）, 4-（3-O-3＂）-3＂-methylbutenyl-6-phenyl- pyran-2-one （5）, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxJn-2（3H）- one （6）, isoimperatorin （7）, 2,3-dimethoxyxanthone （8）, 3,4-dihydroxy-2- methoxyxanthone （9）, osajaxanthone （10）, nigrolineaxanthone F （1 1）, hypercohone G （12）, betulinic acid （1 3）, oleanolic acid 3.13-caffeate （14）, and isoastilbin （1 5）. Conclusion Compound 1 is a new menthane monoterpene derivative which owns an extra lactone ring. Compounds 2-7 and 10-1 5 are isolated from genus Hypericum Linn. for the first time and the other compounds are first obtained from the plants in H. beanii.展开更多
A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3＇-pyrrolol2,3-b]pyridin]-2＇（1＇H）-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ...A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3＇-pyrrolol2,3-b]pyridin]-2＇（1＇H）-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald-Hartwig amidation of carboxylic amide and aryl chloride. A small library was obtained by reductive amination of 1 with various aldehydes and was screened against human lung cancer cell A549, human liver cancer cell BEL7402, and human colon cancer cell HCT-8. The results show that most of the library compounds 2 have some inhibitory activities. 2-（Trifluoromethoxy） benzylic substituted spirocyclic azaoxindole 2e was identified as a nanomolar inhibitor against human lung cancer cell A-549 （IC50 = 50 nmol/L）.展开更多
In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and...In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and Ullmann reaction, which is expected to own high thermal and morphological stability, and good carrier injection/ transporting properties due to the excellent hole transporting characteristics of carbazole and cruciform structure of spiro[fluorene-9,9＇-xanthene]. The carbazole end-capped spiro[fluorene-9,9＇-xanthene] SFX-Cz based PhOLEDs with Flrpic as phosphor emitter have been researched by varying dopant concentration, which exhibit the maximum EQEs of 8.9%, 7.4%, 9.1%, and 4.7% with the doping increasing from 10% to 50%. The higher performance PhOLEDs are independent on concentration variation from 10% to 30%, which suggests the bulky steric hindrance of SFX-Cz might be a potential canditate for high performance and inexpensive device with simplified process.展开更多
The enantioselective double Michael reaction of N-Boc-3-nonsubstitued oxindoles with dienones catalyzed by chiral monoimide protected cyclohexane-1,2-diamines was developed. A wide range of optically active spirocycli...The enantioselective double Michael reaction of N-Boc-3-nonsubstitued oxindoles with dienones catalyzed by chiral monoimide protected cyclohexane-1,2-diamines was developed. A wide range of optically active spirocyclic oxindoles were obtained up to 98% yield and up to 89% ee.展开更多
Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and ...Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and photoelectric properties of the device.Generally,various encapsulation methods from molecular structure to macroscopic device level are used to improve photooxidation stability.Here,we adopted a crystallization strategy to allow 14H-spiro[dibenzo[c,h]acridine-7,9′-fluorene](SFDBA)to pack tightly to resist fluorescence decay caused by oxidation.In this case,the inert group of SFDBA acts as a“steric armor”,protecting the photosensitive group from being attacked by oxygen.Therefore,compared with the fluorescence quenching of SFDBA powder under 2 h of sunlight,SFDBA crystal can maintain its fluorescence emission for more than 8 h under the same conditions.Furthermore,the photoluminescence quantum yields(PLQYs)of the crystalline film is 327%higher than that of the amorphous film.It shows that the crystallization strategy is an effective method to resist oxidation.展开更多
A novel spiro-compound（C20 H15 N2 O3 P） has been synthesized and characterized by means of IR and 1H NMR. Its crystal structure was determined by X-ray diffractometry. The crystal belongs to the monoclinic system, s...A novel spiro-compound（C20 H15 N2 O3 P） has been synthesized and characterized by means of IR and 1H NMR. Its crystal structure was determined by X-ray diffractometry. The crystal belongs to the monoclinic system, space group P21 /c with a = 9.1628（7）, b = 12.9490（7）, c = 15.7898（11）, β = 103.952（8）o, Mr = 36.08, V = 1818.2（2）3, Z = 4, Dc = 1.382 g/cm3, F（000） = 788, μ = 0.179 mm-1, R = 0.0701 and wR = 0.1513. The preliminary biological test showed that the title compound has activities against Escherichia coli, S.albus, Bacillus subtilis, Staphylocc- ocusaureus and Micrococcus tetragenus with MIC to be 0.038, 0.038, 0.075, 2.48, and 0.15 mg/mL, respectively.展开更多
In order to develop novel spirocyclic tetronic acid lead compounds,a series of new spirocyclic tetronic acid derivatives containing oxime ether moiety was synthesized and bioassayed.The stmctures of 16 target compound...In order to develop novel spirocyclic tetronic acid lead compounds,a series of new spirocyclic tetronic acid derivatives containing oxime ether moiety was synthesized and bioassayed.The stmctures of 16 target compounds were characterized by lH NMR spectra,13C NMR spectra and high-resolution mass spectrometer(HRMS).Preliminary bioassays indicated that most of the title compounds displayed excellent insecticidal activity against Aphis fabae and Nilapmyata lugens at 100 mg/L.In particular,compound 6k showed the similar activity(LC50=6.87 mg/L)against A.fabae as the spirotetramat(LC50=4.56 mg/L)and had better efIects(LC50=l.64 mg/L)against N.lugens in comparison with spirotetramat(LC5o=7.90 mg/L).The study showed that compound 6k exhibited more promising and broad-spectrum insecticide activity and may serve as a new insecticidal agent for sucking pests.展开更多
A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an ar...A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an aromatic aldehyde (2), and 3,9-dichloro-2,4,8,10-tetraoxa- 3, 9 -diphosphaspiro [5,5] undecane (3) in anhydrous benzene.展开更多
The present study aimed at identifying cell cycle inhibitors from the fermentation broth of Streptomyces pseudoverticillus YN17707. Activity-guided isolation was performed on ts FT210 cells. Compounds were isolated th...The present study aimed at identifying cell cycle inhibitors from the fermentation broth of Streptomyces pseudoverticillus YN17707. Activity-guided isolation was performed on ts FT210 cells. Compounds were isolated through various chromatographic methods and elucidated by spectroscopic analyses. Flow cytometry was used to evaluate the cell cycle inhibitory activities of the fractions and compounds. Two compounds were obtained and identified as pteridic acid hydrate(1) and pteridic acid C(2), which arrested the ts FT210 cells at the G0/G1 phase with the MIC values being 32.8 and 68.9 μmol·L-1, respectively. These results provide a basis for future development of Compounds 1 and 2 as novel cell cycle inhibitors for cancer therapy.展开更多
The enantioselective double Michael reaction of benzofuranone with dienones catalyzed by Cinchona-based primary amines was developed. A number of optically active spirocyclic benzofuranones were obtained in up to 89% ...The enantioselective double Michael reaction of benzofuranone with dienones catalyzed by Cinchona-based primary amines was developed. A number of optically active spirocyclic benzofuranones were obtained in up to 89% yield and 91% ee.展开更多
Aminosilane bearing bulky substituents on nitrogen： LH2 （L = Me2Si（NDipp＇）2, Dipp = 2,6-diisopropylphenyl） was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si（NDipp）2 was used to synt...Aminosilane bearing bulky substituents on nitrogen： LH2 （L = Me2Si（NDipp＇）2, Dipp = 2,6-diisopropylphenyl） was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si（NDipp）2 was used to synthesize the unusual spirocyclic heterotriatomic complex [MeESi（NDipp）2]ESn （1） by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si（NDipp）2SnPh2 （2） with Ph2SnC12. 1 belongs to the monoclinic system, space group P21/n with a = 13.193（2）, b = 20.663（3）, c = 20.403（3）A, β = 99.954（2）°, V = 5478.3（15） A3, C55H85.5N4Si2Sn, Mr = 977.64, Z = 4, Dc. = 1.185 Mg/m3, μ（MoKa） = 0.547 mm-1, F（000） = 2086, S = 1.000, the final R = 0.0614 and wR = 0.1322 for 14446 observed reflections （1 〉 2σ（I）） and R = 0.0797 and wR = 0.1456 for all data. 2 belongs to the triclinic system, space group P1 with a = 10.36（15）, b = 13.204（7）, c = 14.363（7） A, a = 90.214（10）, β = 106.182（7）, y = 109.854（8）°, V = 1764.4（15） A3, C38HsoN2SiSn, M,. = 681.58, Z = 2, Dc = 1.283 Mg/m^3,μ（MoKa） = 0.785 mm-1, F（000） = 712, S = 1.002, the final R = 0.0498 and wR = 0.0955 for 7533 observed reβections （I 〉 2σ（I）） and R = 0.0676 and wR = 0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN2Si rings. The two complexes were characterized by ^1H NMR, elemental analysis, and single-crystal X-ray structural analysis.展开更多
The double [3 + 2] cycloaddition of allenoates with nitrile oxides is presented. The reaction worked well under mild reaction conditions to give the spirobidihydroisoxazole in moderate to excellent yields with excelle...The double [3 + 2] cycloaddition of allenoates with nitrile oxides is presented. The reaction worked well under mild reaction conditions to give the spirobidihydroisoxazole in moderate to excellent yields with excellent diastereoselectivities. The two dihydroisoxazole rings have been formed via a sequential double [3 + 2] cycloaddition.展开更多
One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by ...One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors.展开更多
Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development. In this article, we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based ...Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development. In this article, we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based cyclometalated ruthenium pincer catalyst system, SNRu-X. After screening catalyst and condition, a high valent Ru(Ⅳ) dioxide(X = O_(2)) species has demonstrated superior reactivity in the catalytic alkenylation of aromatic and olefinic C–H bonds with unactivated alkenyl bromides and triflates. This reaction has achieved the easy construction of a wide range of(hetero)aromatic alkenes and dienes, in good to excellent yields with exclusive selectivity. Preliminary mechanistic studies indicate that this reaction may proceed through a single electron transfer(SET) triggered oxidative addition, by doing so, providing valuable complementary to classical alkenylation reactions that are dependent on activated alkenyl precursors.展开更多
A new type of dianionic Ir(Ⅲ) CCC pincer complexes(SNHC-Ir, 1a–1c) is successfully designed and synthesized by developing a one-step methodology, which involves an initial coordination of Ir(I) with the NHC and subs...A new type of dianionic Ir(Ⅲ) CCC pincer complexes(SNHC-Ir, 1a–1c) is successfully designed and synthesized by developing a one-step methodology, which involves an initial coordination of Ir(I) with the NHC and subsequent metallation of double sp2C–H bonds. This method is considerably useful over those reported by using strong coordination ligand or carbonic anion exchange,and would provide an alternative efficient template of organometallics synthesis. Experimental and density functional theory(DFT) calculation results indicate that the spirocyclic framework is a favourable factor for the facile formation and stabilization of these complexes. Primary investigation shows that chloride 1b can well catalyze homo and hetero addition of styrene derivatives and remote olefin isomerization, which represents the first catalytic application of the dianionic CCC pincer complexes.展开更多
基金National Natural Science Foundation of China(31300293,81422046)General Project of Applied Foundation Research,Yunnan Province(2013FB067)+2 种基金Basic Research Project of Ministry of Science and Technology of China(2012FY110300)Major State Basic Research Development Program(2010CB951704)Youth Innovation Promotion Association CAS and SRF for ROCS,SEM to WL.Xiao
文摘Objective To study the chemical constituents from the aerial parts of Hypericum beani/. Methods Various chromatographic techniques were used to separate the constituents and their structures were elucidated on the basis of extensive spectroscopic interpretation. Results Fifteen compounds were isolated from the aerial parts of H. beanii. Their structures were identified as hyperbeanol E （1）, （E）-Iinalool-l-oic acid （2）, （4S,5R）-5-（4＇-methyl-3＇-pentenyl）-4-hydroxy-5-methyl- dihydrofuran-2-one （3）, benzoic acid （4）, 4-（3-O-3＂）-3＂-methylbutenyl-6-phenyl- pyran-2-one （5）, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxJn-2（3H）- one （6）, isoimperatorin （7）, 2,3-dimethoxyxanthone （8）, 3,4-dihydroxy-2- methoxyxanthone （9）, osajaxanthone （10）, nigrolineaxanthone F （1 1）, hypercohone G （12）, betulinic acid （1 3）, oleanolic acid 3.13-caffeate （14）, and isoastilbin （1 5）. Conclusion Compound 1 is a new menthane monoterpene derivative which owns an extra lactone ring. Compounds 2-7 and 10-1 5 are isolated from genus Hypericum Linn. for the first time and the other compounds are first obtained from the plants in H. beanii.
基金supported by the program of research fund for returning scholars of Ministry of Education of China(No.200812)the Open Foundation of Chemical Engineering Subject(No.200903),Qingdao University of Science & Technology,China
文摘A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3＇-pyrrolol2,3-b]pyridin]-2＇（1＇H）-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald-Hartwig amidation of carboxylic amide and aryl chloride. A small library was obtained by reductive amination of 1 with various aldehydes and was screened against human lung cancer cell A549, human liver cancer cell BEL7402, and human colon cancer cell HCT-8. The results show that most of the library compounds 2 have some inhibitory activities. 2-（Trifluoromethoxy） benzylic substituted spirocyclic azaoxindole 2e was identified as a nanomolar inhibitor against human lung cancer cell A-549 （IC50 = 50 nmol/L）.
文摘In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and Ullmann reaction, which is expected to own high thermal and morphological stability, and good carrier injection/ transporting properties due to the excellent hole transporting characteristics of carbazole and cruciform structure of spiro[fluorene-9,9＇-xanthene]. The carbazole end-capped spiro[fluorene-9,9＇-xanthene] SFX-Cz based PhOLEDs with Flrpic as phosphor emitter have been researched by varying dopant concentration, which exhibit the maximum EQEs of 8.9%, 7.4%, 9.1%, and 4.7% with the doping increasing from 10% to 50%. The higher performance PhOLEDs are independent on concentration variation from 10% to 30%, which suggests the bulky steric hindrance of SFX-Cz might be a potential canditate for high performance and inexpensive device with simplified process.
文摘The enantioselective double Michael reaction of N-Boc-3-nonsubstitued oxindoles with dienones catalyzed by chiral monoimide protected cyclohexane-1,2-diamines was developed. A wide range of optically active spirocyclic oxindoles were obtained up to 98% yield and up to 89% ee.
基金supported by the Natural Science Foundation of Nanjing University of Posts and Telecommunications(NY222157,NY221085)State Key Laboratory of Organic Electronics and Information Display(GZR2022010008)+5 种基金Key Laboratory of Low-dimensional Materials Chemistry of Jiangsu Province(JSKC20022)General Program of China Postdoctoral Science Foundation(2022M711684)General Program of Basic Science(Natural Science)of Colleges and Universities of Jiangsu Province(22KJB430036)National Overseas Study Fund(202008320051)National Key Laboratory(2009DS690095)the National Natural Science Foundation of China(62288102).
文摘Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and photoelectric properties of the device.Generally,various encapsulation methods from molecular structure to macroscopic device level are used to improve photooxidation stability.Here,we adopted a crystallization strategy to allow 14H-spiro[dibenzo[c,h]acridine-7,9′-fluorene](SFDBA)to pack tightly to resist fluorescence decay caused by oxidation.In this case,the inert group of SFDBA acts as a“steric armor”,protecting the photosensitive group from being attacked by oxygen.Therefore,compared with the fluorescence quenching of SFDBA powder under 2 h of sunlight,SFDBA crystal can maintain its fluorescence emission for more than 8 h under the same conditions.Furthermore,the photoluminescence quantum yields(PLQYs)of the crystalline film is 327%higher than that of the amorphous film.It shows that the crystallization strategy is an effective method to resist oxidation.
基金Project supported by the National Natural Science Foundation of China(No.21162008)
文摘A novel spiro-compound（C20 H15 N2 O3 P） has been synthesized and characterized by means of IR and 1H NMR. Its crystal structure was determined by X-ray diffractometry. The crystal belongs to the monoclinic system, space group P21 /c with a = 9.1628（7）, b = 12.9490（7）, c = 15.7898（11）, β = 103.952（8）o, Mr = 36.08, V = 1818.2（2）3, Z = 4, Dc = 1.382 g/cm3, F（000） = 788, μ = 0.179 mm-1, R = 0.0701 and wR = 0.1513. The preliminary biological test showed that the title compound has activities against Escherichia coli, S.albus, Bacillus subtilis, Staphylocc- ocusaureus and Micrococcus tetragenus with MIC to be 0.038, 0.038, 0.075, 2.48, and 0.15 mg/mL, respectively.
基金Supported by the National Key Research&Development Program of China(No.2017YFDO2OO5O5)the Natural Science Foundation of Zhejiang Province,China(No.LY 19C140006).
文摘In order to develop novel spirocyclic tetronic acid lead compounds,a series of new spirocyclic tetronic acid derivatives containing oxime ether moiety was synthesized and bioassayed.The stmctures of 16 target compounds were characterized by lH NMR spectra,13C NMR spectra and high-resolution mass spectrometer(HRMS).Preliminary bioassays indicated that most of the title compounds displayed excellent insecticidal activity against Aphis fabae and Nilapmyata lugens at 100 mg/L.In particular,compound 6k showed the similar activity(LC50=6.87 mg/L)against A.fabae as the spirotetramat(LC50=4.56 mg/L)and had better efIects(LC50=l.64 mg/L)against N.lugens in comparison with spirotetramat(LC5o=7.90 mg/L).The study showed that compound 6k exhibited more promising and broad-spectrum insecticide activity and may serve as a new insecticidal agent for sucking pests.
文摘A simple and direct method for preparation of N-substituted spirocyclic dieSter of □-amino phosphonic acid (4) in high yield is introduced. The reaction consists of the threecomponent reachon of phenylurea (1), an aromatic aldehyde (2), and 3,9-dichloro-2,4,8,10-tetraoxa- 3, 9 -diphosphaspiro [5,5] undecane (3) in anhydrous benzene.
基金supported by the National Natural Science Foundation of China(No.30472079)National Basic Research Program of China(No.2006CB504100)
文摘The present study aimed at identifying cell cycle inhibitors from the fermentation broth of Streptomyces pseudoverticillus YN17707. Activity-guided isolation was performed on ts FT210 cells. Compounds were isolated through various chromatographic methods and elucidated by spectroscopic analyses. Flow cytometry was used to evaluate the cell cycle inhibitory activities of the fractions and compounds. Two compounds were obtained and identified as pteridic acid hydrate(1) and pteridic acid C(2), which arrested the ts FT210 cells at the G0/G1 phase with the MIC values being 32.8 and 68.9 μmol·L-1, respectively. These results provide a basis for future development of Compounds 1 and 2 as novel cell cycle inhibitors for cancer therapy.
基金Acknowledgement This work was supported by National Natural Science Foundation of China （Nos. 20802075 and No. 21042006）.
文摘The enantioselective double Michael reaction of benzofuranone with dienones catalyzed by Cinchona-based primary amines was developed. A number of optically active spirocyclic benzofuranones were obtained in up to 89% yield and 91% ee.
基金supported by the National Natural Science Foundation of China (No.21001016 and 20901009)
文摘Aminosilane bearing bulky substituents on nitrogen： LH2 （L = Me2Si（NDipp＇）2, Dipp = 2,6-diisopropylphenyl） was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si（NDipp）2 was used to synthesize the unusual spirocyclic heterotriatomic complex [MeESi（NDipp）2]ESn （1） by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si（NDipp）2SnPh2 （2） with Ph2SnC12. 1 belongs to the monoclinic system, space group P21/n with a = 13.193（2）, b = 20.663（3）, c = 20.403（3）A, β = 99.954（2）°, V = 5478.3（15） A3, C55H85.5N4Si2Sn, Mr = 977.64, Z = 4, Dc. = 1.185 Mg/m3, μ（MoKa） = 0.547 mm-1, F（000） = 2086, S = 1.000, the final R = 0.0614 and wR = 0.1322 for 14446 observed reflections （1 〉 2σ（I）） and R = 0.0797 and wR = 0.1456 for all data. 2 belongs to the triclinic system, space group P1 with a = 10.36（15）, b = 13.204（7）, c = 14.363（7） A, a = 90.214（10）, β = 106.182（7）, y = 109.854（8）°, V = 1764.4（15） A3, C38HsoN2SiSn, M,. = 681.58, Z = 2, Dc = 1.283 Mg/m^3,μ（MoKa） = 0.785 mm-1, F（000） = 712, S = 1.002, the final R = 0.0498 and wR = 0.0955 for 7533 observed reβections （I 〉 2σ（I）） and R = 0.0676 and wR = 0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN2Si rings. The two complexes were characterized by ^1H NMR, elemental analysis, and single-crystal X-ray structural analysis.
基金supported by the National Natural Science Foundation of China(Nos. 21372256, 21572264)
文摘The double [3 + 2] cycloaddition of allenoates with nitrile oxides is presented. The reaction worked well under mild reaction conditions to give the spirobidihydroisoxazole in moderate to excellent yields with excellent diastereoselectivities. The two dihydroisoxazole rings have been formed via a sequential double [3 + 2] cycloaddition.
基金supported by the National Natural Science Foundation of China(No.82204276)the Guangxi Natural Science Foundation(No.2021GXNSFBA075036)+4 种基金the Specific Research Project of Guangxi for Research Bases and Talents(Nos.AD22035018,AD20297036)the 2021 University-Level Scientific Research Projects of Guangxi Minzu University(No.2021MDKJ003)the Talent Scientific Research Initiation Project of Guangxi Minzu University(No.2021KJQD09)the Xiangsi Lake Youth Innovation Team Project of Guangxi Minzu University(No.2021 RSCXSHQN01)the Guangxi Scholarship Fund of Guangxi Education Department.
文摘One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors.
基金suported by the National Natural Science Foundation of China (2187,1117, 91956203)the “111” Program of Minister of Education, Beijing National Laboratory for Molecular Sciences (BNLMS202109)the Science and Technology Commission of Shanghai Municipality (19JC1430100)。
文摘Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development. In this article, we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based cyclometalated ruthenium pincer catalyst system, SNRu-X. After screening catalyst and condition, a high valent Ru(Ⅳ) dioxide(X = O_(2)) species has demonstrated superior reactivity in the catalytic alkenylation of aromatic and olefinic C–H bonds with unactivated alkenyl bromides and triflates. This reaction has achieved the easy construction of a wide range of(hetero)aromatic alkenes and dienes, in good to excellent yields with exclusive selectivity. Preliminary mechanistic studies indicate that this reaction may proceed through a single electron transfer(SET) triggered oxidative addition, by doing so, providing valuable complementary to classical alkenylation reactions that are dependent on activated alkenyl precursors.
基金This work was supported by the National Natural Science Foundation of China(21502080,21772076,21871117,21772071,21702136,91956203)the“111”Program of Ministry of Education of China,the Major Project(2018ZX09711001-005-002)of Ministry of Science and Technology of China+2 种基金the Science and Technology Commission of Shanghai Municipality(19IC1430100)This work was supported by the High-Performance Computing Center of Shanghai Jiao Tong UniversityAlso,we thank Prof.Qing-Wei Zhang from the University of Science and Technology of China for his helpful discussion.
文摘A new type of dianionic Ir(Ⅲ) CCC pincer complexes(SNHC-Ir, 1a–1c) is successfully designed and synthesized by developing a one-step methodology, which involves an initial coordination of Ir(I) with the NHC and subsequent metallation of double sp2C–H bonds. This method is considerably useful over those reported by using strong coordination ligand or carbonic anion exchange,and would provide an alternative efficient template of organometallics synthesis. Experimental and density functional theory(DFT) calculation results indicate that the spirocyclic framework is a favourable factor for the facile formation and stabilization of these complexes. Primary investigation shows that chloride 1b can well catalyze homo and hetero addition of styrene derivatives and remote olefin isomerization, which represents the first catalytic application of the dianionic CCC pincer complexes.
