Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing c...Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing carbon dioxide as double synthons via bimolecular reduction remains challenging. Here, by leveraging the bimolecular reduction of carbon dioxide to carbonyl and methyl respectively, we describe a Pd-catalyzed trifunctionalization of alkynes with aryl iodide for the first time and showcase its advantages on the formation of various β-diketones and their application in the constructing of heterocyclic compounds with important biological activity, including pyrimidine, oxazole, pyrazole.展开更多
The first diastereodivergent formal[4+1]cycloaddition reactions of azoalkenes with p-quinone methides(pQMs)have been accomplished.The reported reaction occurred via a domino oxa-1,4-addition/1,6-addition process,allow...The first diastereodivergent formal[4+1]cycloaddition reactions of azoalkenes with p-quinone methides(pQMs)have been accomplished.The reported reaction occurred via a domino oxa-1,4-addition/1,6-addition process,allowing the use of common azoalkenes as C1 synthons.A broad range of 2,3-dihydrobenzofurans was smoothly prepared in good yields and with reversible diastereoselectivities.The steric hindrance and hydrogenbonding interaction were proposed to account for the two different modes of diastereo-control.The projected reaction features the employment of azoalkene as carbene-like C1 synthon,mild conditions,broad substrate scope and tunable diastereoselectivity.展开更多
1-Methylpiperazine was employed to crystallize with 2,4-dihydroxybenzoic acid and 1,8-naphthalene acid, affording two multi-component hydrogen-bonding salts [(C5H14N2)^2+-(C7H5O4)2^·H2O](1) and [(C5H14N2...1-Methylpiperazine was employed to crystallize with 2,4-dihydroxybenzoic acid and 1,8-naphthalene acid, affording two multi-component hydrogen-bonding salts [(C5H14N2)^2+-(C7H5O4)2^·H2O](1) and [(C5H14N2)^2+(C12H6O4)^2-.2H2O](2). These two forms of salts are both monoclinic systems with space group P21/c(14). The lattice parameters of salts 1 and 2 are a=1.32666(10) nm, b=0.90527(7) nm, c=1.67107(13) nm, β=103.125(1)° and a=1.4950(2) nm, b=0.75242(15) nm, c=1.6563(3) nm, β=92.834(2)°, respectively. Expected classical hydrogen bonds N-H...O and O-H...O appear in the chargetransfer salts, and asymmetric units of these two forms both contain water molecules which play a significant role in building novel supramolecular architectures. Robust hydrogen-bond interactions between 1-methylpiperazine and aromatic acid provide sufficient driving force to direct the two crystals to three-dimensional structures. Weak interactions C-H-O emerging in salts 1 and 2 further enhance their crystal structures. As a consequence, hydrogen-bonding interactions in these compounds afford diverse 3D net supramolecular architectures. Thermal stability of these compounds was investigated by thermogravimetric analysis(TGA).展开更多
The synthesis and aggregation behavior of two glycoluril derivatives were descrybed.The crystal of compound 1 belongs to the triclinic system,space group P1,with a=8.946(1),b=13.445(2),c=20.361(3)?,α=89.517(3),β=84....The synthesis and aggregation behavior of two glycoluril derivatives were descrybed.The crystal of compound 1 belongs to the triclinic system,space group P1,with a=8.946(1),b=13.445(2),c=20.361(3)?,α=89.517(3),β=84.405(3),γ=86.325(3)°,Z=2,V=2432.1(6)?3,Dc=1.293 g·cm-3,C48H34N6O6·2DMSO,Mr=947.07,F(000)=992,μ=0.170 mm-1,the final R=0.1606 and wR=0.2410 for 4382 observed reflections(Ⅰ>2σ(Ⅰ)).The crystal of compound 2belongs to the monoclinic system,space group P21/c,with a=9.500(3),b=24.522(8),c=17.997(6)A,Z=2,V=4054(2)A^3,Dc=1.296 g·cm^-3,C48H34N6O6,Mr=790.81,F(000)=1648,μ=0.087mm-1,the final R=0.2146 and wR=0.2535 for 2878 observed reflections(Ⅰ>2σ(Ⅰ)).Unlike the highly conserved R22(8)hydrogen-bonding amide···amide homosynthon,the structural analysis indicated that compound 1 selected the C(20)hydrogen-bonding motif and 2 selected the R22(34)hydrogen-bonding motif,which revealed the competition from remote solvent molecule and the interference of the molecular hydrocarbon core in crystal packing.The supramolecular structure revealed molecule 1 is further linked into a one-dimensional chain and 2 into a two-dimensional interwoven plane by N–H···N hydrogen bonds.展开更多
From natural tartaric acid, (R)-2-benzyloxy-3-(2-tetrahydropyranyloxy) propanol 3 was designed and synthesized, and (R)-2-benzyloxy-3-(4-methoxybenzyloxy) propanol 7 was prepared in a new method. They can be used as ...From natural tartaric acid, (R)-2-benzyloxy-3-(2-tetrahydropyranyloxy) propanol 3 was designed and synthesized, and (R)-2-benzyloxy-3-(4-methoxybenzyloxy) propanol 7 was prepared in a new method. They can be used as chiral synthons of lysophosphatidic acid and other compounds with asymmetric propanetriol backbone.展开更多
The construction of an unprecedented intertwined spiral solvent channel is driven by weak C–Cl…O and C–H…N interactions based on extraordinary parallel spirals which were structured from supramolecular synthon mac...The construction of an unprecedented intertwined spiral solvent channel is driven by weak C–Cl…O and C–H…N interactions based on extraordinary parallel spirals which were structured from supramolecular synthon macrocycle 1(C44H44N4O4) with a propargylamine backbone. The product is characterized by ^1H NMR, ^13C NMR, IR and HRMS, and further confirmed by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c, with a = 28.922(3), b = 8.5069(9), c = 21.687(2)A^°, β = 130.6320(10)°, V = 4049.4(7) A^°3 and Z = 8. A total of 11874 reflections were collected, of which 4942 were independent(Rint = 0.0590) and 2937 were observed with I 〉 2σ(I). The final full-matrix least-squares refinement gave R(I 〉 2s(I)) = 0.069 and w R = 0.167, S = 1.05,(Δρ)max = 0.20 and(Δρ)min =-0.22 e·A^1-3. The fluorescence of the product is discussed.展开更多
An efficient synthesis of functionalized 6-decalone 16, starting from a dienolate anion 3a via a tandem Michael reaction, is described. 16 could be used as a potential intermediate for synthesis of drimane related ses...An efficient synthesis of functionalized 6-decalone 16, starting from a dienolate anion 3a via a tandem Michael reaction, is described. 16 could be used as a potential intermediate for synthesis of drimane related sesquiterpenes.展开更多
A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type II photochemical reaction.
Diversity-oriented synthesis is a powerful and interesting synthetic tool for the rapid construction of structurally complex and privileged scaffolds from readily accessible starting materials.To date,diversity-orient...Diversity-oriented synthesis is a powerful and interesting synthetic tool for the rapid construction of structurally complex and privileged scaffolds from readily accessible starting materials.To date,diversity-oriented synthesis mostly relies on the employment of versatile reagents.Versatile reagents can be regulated as controllable and flexible building blocks for multipurpose utilizations.Over the past decade,a variety of multifunctional reagents have been developed.However,most versatile reagents usually need multi-step synthesis,thus restricting their wide application to a large extent.In terms of the practicalities and universalities,we prefer to pay more attention to the utilization of simple and practical versatile reagents with multiple reactivities,mainly including atropaldehyde acetals,aryl methyl ketones,vinylene carbonate,vinyl azides,aryldiazonium salts,rongalite,halodifluoromethyl compounds.Most importantly,these versatile reagents can also play different roles simultaneously in the same reaction,in which their different reactivities are converged into the final target products.Such strategy can not only offer more possibilities for the synthesis of several active pharmaceutical ingredients,but also minimize the occurrence of some side reactions by lessening the varieties of materials.Also,a perspective is given at the end of this review.展开更多
The virtual cocrystal screening approach based on molecular electrostatic potential surface(MEPS)maps is a fast and feasible computational method to estimate the probability of cocrystal formation by calculating the d...The virtual cocrystal screening approach based on molecular electrostatic potential surface(MEPS)maps is a fast and feasible computational method to estimate the probability of cocrystal formation by calculating the difference in the interaction site pairing energies of monomers and that of their assemblies prior to experimental screening.In this paper,we report 12 cocrystal forms of temozolomide with mono-,di-,and trihydroxy benzoic acids,namely,3-hydroxy-,2,4-dihydroxy-,2,5-dihydroxy-,2,6-dihydroxy-,3,4-dihydroxy-,and 3,4,5-trihydroxy-benzoic acids,as well as benzoic acid,as pharmaceutical coformers for the first time.10 single crystals out of the 12 cocrystal forms were obtained and unequivocally determined by single-crystal X-ray diffraction,which clarified spatial arrangements,molecular conformations,and supramolecular synthons.MEPS further gains some insights into the sites of hydrogen bonding interactions for exploring combination patterns in these assemblies.Modulated stability of TMZ was successfully achieved by cocrystallization with these acids.展开更多
Carbon dioxide(CO_(2))is an attractive C1 building block in chemical synthesis due to its abundance,availability and sustainability.However,the low reactivity and high stability generally limits its transformations un...Carbon dioxide(CO_(2))is an attractive C1 building block in chemical synthesis due to its abundance,availability and sustainability.However,the low reactivity and high stability generally limits its transformations under mild conditions to value added chemicals.Recent advances in flow chemistry provide effective means for the chemical transformation of CO_(2),and many new methods and techniques that fully utilized the advantages of continuous flow platforms for the chemical fixation of CO_(2)have been realized.In view of the rapid development and the urgent need for continuous transformation of CO_(2),herein we wish to present an update of the recent advances in this research area.展开更多
Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state drugs.Their improvements of solubility,bioavailability,and the reduced tendency for...Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state drugs.Their improvements of solubility,bioavailability,and the reduced tendency for phase transformation occurrence,are factors that highlight benefits of pharmaceutical co-crystals among other solid forms.According to the Biopharmaceutical Classification System(BCS),non-steroidal anti-inflammatory drugs(NSAIDs)are class Ⅱ drugs,which have low aqueous solubility and therefore co-crystallization has the potential to optimize NSAID product properties.In this review,we highlight the recent progress made on NSAIDs co-crystals,their co-formers,synthesis,methods and use,while we underline some promising results on in vitro and in vivo co-crystal properties.A celecoxib-tramadol co-crystal reaches phase Ⅲ clinical trials,showing greater analgesic activity than both individual APIs.The aqueous solubility of the co-crystal formed between l-proline and diclofenac is very high in comparison with the pure drug.Naproxen co-crystals with urea and thiourea have an increase of drug release of almost 60%.Co-crystal design brings a new perspective in drug development since the co-former used can also be a biologically active component allowing to combine different anti-inflammatory drugs,which have an incredible spectrum of application due to the analgesic,anti-pyretic and anti-inflammatory properties.展开更多
This essay discusses some preliminary thoughts on the development of a rational and modular approach for molecular design in soft matter engineering and proposes ideas of structural and functional synthons for advance...This essay discusses some preliminary thoughts on the development of a rational and modular approach for molecular design in soft matter engineering and proposes ideas of structural and functional synthons for advanced functional materials. It echoes the Materials Genome Initiative by practicing a tentative retro-functional analysis (RFA) scheme. The importance of hierarchical structures in transferring and amplifying molecular functions into macroscopic properties is recognized and emphasized. According to the role of molecular segments in final materials, there are two types of building blocks: structural synthon and functional synthon. Guided by a specific structure for a desired function, these synthons can be modularly combined in various ways to construct molecular scaffolds. Detailed molecular structures are then deduced, designed and synthesized precisely and modularly. While the assembled structure and property may deviate from the original design, the study may allow further refinement of the molecular design toward the target function, The strategy has been used in the development of soft fullerene materials and other giant molecules. There are a few aspects that are not yet well addressed: (1) function and structure are not fully decoupled and (2) the assembled hierarchical structures are sensitive to secondary interactions and molecular geometries across different length scales. Nevertheless, the RFA approach provides a starting point and an alternative thinking pathway by provoking creativity with considerations from both chemistry and physics. This is particularly useful for engineering soft matters with supramolecular lattice formation, as in giant molecules, where the synthons are relatively independent of each other.展开更多
A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomeri...A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomerically pure bispiro[benzofuran-oxindole/benzofuran-chromanone]s bearing five consecutive stereocenters including two spiro quaternary carton centers in good yields(up to 93%) with high diastereoselectivities(up to>20:1 dr) and good enantioselectivities(up to>99% ee).Moreover,this is the first example of bifunctional chromone-benzofuranone synthon directed organocatalytic tandem reaction,and also the first example of the bispiro[benzofuran-oxindole] and bispirobenzofuranone,potentially useful in medicinal chemistry.展开更多
A metal-free cross coupling between common CH2Cl2 and carboxylic acids has been achieved with K2CO3 as the sole additive. This simple protocol is a convenient and cost-effective route to synthesize methylene diesters ...A metal-free cross coupling between common CH2Cl2 and carboxylic acids has been achieved with K2CO3 as the sole additive. This simple protocol is a convenient and cost-effective route to synthesize methylene diesters from a wide scope of carboxylic acids substrates with good functional group tolerance. Several gram-scale reactions have been performed to evaluate the effectiveness and practicality of this protocol.展开更多
Structural information on the crystalline forms of mebendazole, an anti-parasitic drug, is limited, although three polymorphic forms of this drug have been reported. The present work investigates the structures and pr...Structural information on the crystalline forms of mebendazole, an anti-parasitic drug, is limited, although three polymorphic forms of this drug have been reported. The present work investigates the structures and properties of different crystalline forms of mebendazole with a series of n-alkyl carboxylic acids, including trifluroacetic acid (1), formic acid (2), acetic acid (3), propanoic acid (4), butanoic acid (5), valeric acid (6) and hexanoic acid (7). These compounds were characterized by thermogravimetric analysis, IR spectra, as well as powder and single-crystal X-ray diffraction analysis. The R22(8) structural motif was detected in all the seven products, which was formed by a pair of N--H…O/O--H…N hydrogen bonds between mebendazole and carboxylic acid. Forms 3--7 were found to be neutral solvate, while in forms 1 and 2, proton transfer was observed from carboxylic acid to mebendazole.展开更多
The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a...The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex展开更多
A selective ring-opening [3+2] cyclization reaction of benzo[d]isoxazoles with 2-bromo-propanamides has been developed.The azaoxyallyl cation intermediates are employed as C^O 3-atom synthon to build oxa-heterocycles ...A selective ring-opening [3+2] cyclization reaction of benzo[d]isoxazoles with 2-bromo-propanamides has been developed.The azaoxyallyl cation intermediates are employed as C^O 3-atom synthon to build oxa-heterocycles via the selectivity of suitable cyclization partners.This transformation provides rapid access to highly functionalized 2-hydroxyaryl-oxazolines under mild conditions and excellent regioselectivity.展开更多
This highlight summarizes a recent development of KF-promoted three-component fluorinationaminocarbonylation reaction of aldehydes,tertiary amines,and TMSCF_(2)Br for the synthesis of structurally importantα-fluoroam...This highlight summarizes a recent development of KF-promoted three-component fluorinationaminocarbonylation reaction of aldehydes,tertiary amines,and TMSCF_(2)Br for the synthesis of structurally importantα-fluoroamide derivatives.The key to the success of this method could be attributed to the multiple functions of difluorocarbene precursor(TMSCF_(2)Br)as both a C1 synthon and a F1 reagent through the process of C-F bond cleavage and C-F bond re-formation.展开更多
基金supported by the National Natural Science Foundation of China(21971073,22001075,22231002)the Natural Science Foundation of Guangdong Province(2019A1515011468)+2 种基金the Discipline Construction Project of Guangdong Medical University(4SG23231G,4SG23249G)the Ordinary University Characteristic Innovation Project of Guangdong Province(2022KTSCX047)the Key-Area Research and Development Program of Guangdong Province(2020B010188001)。
文摘Carbon dioxide reduction, as a sustainable and versatile strategy for the access of chemical fuels, has attracted increasing attention and enormous efforts have been devoted to it in recent years. However, employing carbon dioxide as double synthons via bimolecular reduction remains challenging. Here, by leveraging the bimolecular reduction of carbon dioxide to carbonyl and methyl respectively, we describe a Pd-catalyzed trifunctionalization of alkynes with aryl iodide for the first time and showcase its advantages on the formation of various β-diketones and their application in the constructing of heterocyclic compounds with important biological activity, including pyrimidine, oxazole, pyrazole.
基金support from the Natural Science Foundation of Henan Province(No.222300420084)the Application Research Plan of Key Scientific Research Projects in Colleges and Universities of Henan Province(No.22A150056)is gratefully acknowledged.
文摘The first diastereodivergent formal[4+1]cycloaddition reactions of azoalkenes with p-quinone methides(pQMs)have been accomplished.The reported reaction occurred via a domino oxa-1,4-addition/1,6-addition process,allowing the use of common azoalkenes as C1 synthons.A broad range of 2,3-dihydrobenzofurans was smoothly prepared in good yields and with reversible diastereoselectivities.The steric hindrance and hydrogenbonding interaction were proposed to account for the two different modes of diastereo-control.The projected reaction features the employment of azoalkene as carbene-like C1 synthon,mild conditions,broad substrate scope and tunable diastereoselectivity.
基金Supported by the National Natural Science Foundation of China(Nos.51372125, 21203106), the Fund of the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, China(No.2013-34), and the Scientific and Technical Development Project of Qingdao City, China(No. 13-1-4-184-jch).
文摘1-Methylpiperazine was employed to crystallize with 2,4-dihydroxybenzoic acid and 1,8-naphthalene acid, affording two multi-component hydrogen-bonding salts [(C5H14N2)^2+-(C7H5O4)2^·H2O](1) and [(C5H14N2)^2+(C12H6O4)^2-.2H2O](2). These two forms of salts are both monoclinic systems with space group P21/c(14). The lattice parameters of salts 1 and 2 are a=1.32666(10) nm, b=0.90527(7) nm, c=1.67107(13) nm, β=103.125(1)° and a=1.4950(2) nm, b=0.75242(15) nm, c=1.6563(3) nm, β=92.834(2)°, respectively. Expected classical hydrogen bonds N-H...O and O-H...O appear in the chargetransfer salts, and asymmetric units of these two forms both contain water molecules which play a significant role in building novel supramolecular architectures. Robust hydrogen-bond interactions between 1-methylpiperazine and aromatic acid provide sufficient driving force to direct the two crystals to three-dimensional structures. Weak interactions C-H-O emerging in salts 1 and 2 further enhance their crystal structures. As a consequence, hydrogen-bonding interactions in these compounds afford diverse 3D net supramolecular architectures. Thermal stability of these compounds was investigated by thermogravimetric analysis(TGA).
基金supported by the Natural Science Foundation of Hubei Province(No.2017CFB355)the State Undergraduate Innovative Training Program(No.201610517012)
文摘The synthesis and aggregation behavior of two glycoluril derivatives were descrybed.The crystal of compound 1 belongs to the triclinic system,space group P1,with a=8.946(1),b=13.445(2),c=20.361(3)?,α=89.517(3),β=84.405(3),γ=86.325(3)°,Z=2,V=2432.1(6)?3,Dc=1.293 g·cm-3,C48H34N6O6·2DMSO,Mr=947.07,F(000)=992,μ=0.170 mm-1,the final R=0.1606 and wR=0.2410 for 4382 observed reflections(Ⅰ>2σ(Ⅰ)).The crystal of compound 2belongs to the monoclinic system,space group P21/c,with a=9.500(3),b=24.522(8),c=17.997(6)A,Z=2,V=4054(2)A^3,Dc=1.296 g·cm^-3,C48H34N6O6,Mr=790.81,F(000)=1648,μ=0.087mm-1,the final R=0.2146 and wR=0.2535 for 2878 observed reflections(Ⅰ>2σ(Ⅰ)).Unlike the highly conserved R22(8)hydrogen-bonding amide···amide homosynthon,the structural analysis indicated that compound 1 selected the C(20)hydrogen-bonding motif and 2 selected the R22(34)hydrogen-bonding motif,which revealed the competition from remote solvent molecule and the interference of the molecular hydrocarbon core in crystal packing.The supramolecular structure revealed molecule 1 is further linked into a one-dimensional chain and 2 into a two-dimensional interwoven plane by N–H···N hydrogen bonds.
文摘From natural tartaric acid, (R)-2-benzyloxy-3-(2-tetrahydropyranyloxy) propanol 3 was designed and synthesized, and (R)-2-benzyloxy-3-(4-methoxybenzyloxy) propanol 7 was prepared in a new method. They can be used as chiral synthons of lysophosphatidic acid and other compounds with asymmetric propanetriol backbone.
基金supported by the Natural Science Foundation of Anhui Province Education Department(No.KJ2014A141,No.KJ2015A243,No.KJ2016A862)
文摘The construction of an unprecedented intertwined spiral solvent channel is driven by weak C–Cl…O and C–H…N interactions based on extraordinary parallel spirals which were structured from supramolecular synthon macrocycle 1(C44H44N4O4) with a propargylamine backbone. The product is characterized by ^1H NMR, ^13C NMR, IR and HRMS, and further confirmed by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c, with a = 28.922(3), b = 8.5069(9), c = 21.687(2)A^°, β = 130.6320(10)°, V = 4049.4(7) A^°3 and Z = 8. A total of 11874 reflections were collected, of which 4942 were independent(Rint = 0.0590) and 2937 were observed with I 〉 2σ(I). The final full-matrix least-squares refinement gave R(I 〉 2s(I)) = 0.069 and w R = 0.167, S = 1.05,(Δρ)max = 0.20 and(Δρ)min =-0.22 e·A^1-3. The fluorescence of the product is discussed.
文摘An efficient synthesis of functionalized 6-decalone 16, starting from a dienolate anion 3a via a tandem Michael reaction, is described. 16 could be used as a potential intermediate for synthesis of drimane related sesquiterpenes.
文摘A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type II photochemical reaction.
基金supported by the National Natural Science Foundation of China(No.22072049)National Key Research and Development Project(No.2022YFE0124100)+2 种基金Major Special Projects of Science and Technology of Ordos(No.2022EEDSKJZDZX003)Program for HUST Academic Frontier Youth Team(No.2019QYTD06)is also acknowledgedChen is also grateful for the financial support from China Scholarship Council(CSC).
文摘Diversity-oriented synthesis is a powerful and interesting synthetic tool for the rapid construction of structurally complex and privileged scaffolds from readily accessible starting materials.To date,diversity-oriented synthesis mostly relies on the employment of versatile reagents.Versatile reagents can be regulated as controllable and flexible building blocks for multipurpose utilizations.Over the past decade,a variety of multifunctional reagents have been developed.However,most versatile reagents usually need multi-step synthesis,thus restricting their wide application to a large extent.In terms of the practicalities and universalities,we prefer to pay more attention to the utilization of simple and practical versatile reagents with multiple reactivities,mainly including atropaldehyde acetals,aryl methyl ketones,vinylene carbonate,vinyl azides,aryldiazonium salts,rongalite,halodifluoromethyl compounds.Most importantly,these versatile reagents can also play different roles simultaneously in the same reaction,in which their different reactivities are converged into the final target products.Such strategy can not only offer more possibilities for the synthesis of several active pharmaceutical ingredients,but also minimize the occurrence of some side reactions by lessening the varieties of materials.Also,a perspective is given at the end of this review.
基金supported by the Beijing Natural Science Foundation(No.7222261)CAMS Innovation Fund for Medical Sciences(Nos.2022-I2M-01-015 and 2022-I2M-JB-010)+1 种基金Key R&D Program of Shan Dong Province(No.2019JZZY020909)Chinese Pharmacopoeia Commission Drug Standard Promoting Fund(No.2022Y01)。
文摘The virtual cocrystal screening approach based on molecular electrostatic potential surface(MEPS)maps is a fast and feasible computational method to estimate the probability of cocrystal formation by calculating the difference in the interaction site pairing energies of monomers and that of their assemblies prior to experimental screening.In this paper,we report 12 cocrystal forms of temozolomide with mono-,di-,and trihydroxy benzoic acids,namely,3-hydroxy-,2,4-dihydroxy-,2,5-dihydroxy-,2,6-dihydroxy-,3,4-dihydroxy-,and 3,4,5-trihydroxy-benzoic acids,as well as benzoic acid,as pharmaceutical coformers for the first time.10 single crystals out of the 12 cocrystal forms were obtained and unequivocally determined by single-crystal X-ray diffraction,which clarified spatial arrangements,molecular conformations,and supramolecular synthons.MEPS further gains some insights into the sites of hydrogen bonding interactions for exploring combination patterns in these assemblies.Modulated stability of TMZ was successfully achieved by cocrystallization with these acids.
基金The financial support from the National Key Research and Development Program of China(No.2020YFA0710200)National Natural Science Foundation of China(No.22171090)+1 种基金the Shanghai Science and Technology Innovation Action Plan(No.20JC1416900)the Fundamental Research Funds for the Central Universities is highly appreciated。
文摘Carbon dioxide(CO_(2))is an attractive C1 building block in chemical synthesis due to its abundance,availability and sustainability.However,the low reactivity and high stability generally limits its transformations under mild conditions to value added chemicals.Recent advances in flow chemistry provide effective means for the chemical transformation of CO_(2),and many new methods and techniques that fully utilized the advantages of continuous flow platforms for the chemical fixation of CO_(2)have been realized.In view of the rapid development and the urgent need for continuous transformation of CO_(2),herein we wish to present an update of the recent advances in this research area.
基金FAPESP(Proc.n 2013/09022-7,2017/14936-9,2018/12463-9,2018/24378-6 and 2018/23357-5)CNPq(Proc.141829/2017-6)for financial support+1 种基金the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No.722456 CORE ITN for funding as part of the CORE project(October 2016-September 2020)the EPSRC Centre for Innovative Manufacturing in Continuous Manufacturing and Crystallization(http://www.cmac.ac.uk)for supporting this work(EPSRC funding under Grant Reference:EP/1033459/1).
文摘Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state drugs.Their improvements of solubility,bioavailability,and the reduced tendency for phase transformation occurrence,are factors that highlight benefits of pharmaceutical co-crystals among other solid forms.According to the Biopharmaceutical Classification System(BCS),non-steroidal anti-inflammatory drugs(NSAIDs)are class Ⅱ drugs,which have low aqueous solubility and therefore co-crystallization has the potential to optimize NSAID product properties.In this review,we highlight the recent progress made on NSAIDs co-crystals,their co-formers,synthesis,methods and use,while we underline some promising results on in vitro and in vivo co-crystal properties.A celecoxib-tramadol co-crystal reaches phase Ⅲ clinical trials,showing greater analgesic activity than both individual APIs.The aqueous solubility of the co-crystal formed between l-proline and diclofenac is very high in comparison with the pure drug.Naproxen co-crystals with urea and thiourea have an increase of drug release of almost 60%.Co-crystal design brings a new perspective in drug development since the co-former used can also be a biologically active component allowing to combine different anti-inflammatory drugs,which have an incredible spectrum of application due to the analgesic,anti-pyretic and anti-inflammatory properties.
基金financially supported by the 863 Program(No.2015AA020941)the National Natural Science Foundation of China(Nos.21474003 and 91427304)+1 种基金National Science Foundation of USA(Nos.DMR-0906898 and DMR-1408872)the Joint-Hope Education Foundation.W.B.Z.acknowledges support from the National"1000 Plan(Youth)"of China
文摘This essay discusses some preliminary thoughts on the development of a rational and modular approach for molecular design in soft matter engineering and proposes ideas of structural and functional synthons for advanced functional materials. It echoes the Materials Genome Initiative by practicing a tentative retro-functional analysis (RFA) scheme. The importance of hierarchical structures in transferring and amplifying molecular functions into macroscopic properties is recognized and emphasized. According to the role of molecular segments in final materials, there are two types of building blocks: structural synthon and functional synthon. Guided by a specific structure for a desired function, these synthons can be modularly combined in various ways to construct molecular scaffolds. Detailed molecular structures are then deduced, designed and synthesized precisely and modularly. While the assembled structure and property may deviate from the original design, the study may allow further refinement of the molecular design toward the target function, The strategy has been used in the development of soft fullerene materials and other giant molecules. There are a few aspects that are not yet well addressed: (1) function and structure are not fully decoupled and (2) the assembled hierarchical structures are sensitive to secondary interactions and molecular geometries across different length scales. Nevertheless, the RFA approach provides a starting point and an alternative thinking pathway by provoking creativity with considerations from both chemistry and physics. This is particularly useful for engineering soft matters with supramolecular lattice formation, as in giant molecules, where the synthons are relatively independent of each other.
基金financial support from the National Nature Science Foundation of China(Nos.81760625,81660576 and81560563)Projects of Guizhou Province(Nos.[2016]5623,JG[2016]06,[2019]1402,[2017]5609 and[2018]5781)。
文摘A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomerically pure bispiro[benzofuran-oxindole/benzofuran-chromanone]s bearing five consecutive stereocenters including two spiro quaternary carton centers in good yields(up to 93%) with high diastereoselectivities(up to>20:1 dr) and good enantioselectivities(up to>99% ee).Moreover,this is the first example of bifunctional chromone-benzofuranone synthon directed organocatalytic tandem reaction,and also the first example of the bispiro[benzofuran-oxindole] and bispirobenzofuranone,potentially useful in medicinal chemistry.
基金Financial support from the National Natural Science Foundation of China(NSFC, Nos. 21761021 and 21571094)Natural Science Foundation of Jiangxi Province(No. 20171BAB203002)Sci & Tech Project of Education Department of Jiangxi Province(No. 60007)
文摘A metal-free cross coupling between common CH2Cl2 and carboxylic acids has been achieved with K2CO3 as the sole additive. This simple protocol is a convenient and cost-effective route to synthesize methylene diesters from a wide scope of carboxylic acids substrates with good functional group tolerance. Several gram-scale reactions have been performed to evaluate the effectiveness and practicality of this protocol.
文摘Structural information on the crystalline forms of mebendazole, an anti-parasitic drug, is limited, although three polymorphic forms of this drug have been reported. The present work investigates the structures and properties of different crystalline forms of mebendazole with a series of n-alkyl carboxylic acids, including trifluroacetic acid (1), formic acid (2), acetic acid (3), propanoic acid (4), butanoic acid (5), valeric acid (6) and hexanoic acid (7). These compounds were characterized by thermogravimetric analysis, IR spectra, as well as powder and single-crystal X-ray diffraction analysis. The R22(8) structural motif was detected in all the seven products, which was formed by a pair of N--H…O/O--H…N hydrogen bonds between mebendazole and carboxylic acid. Forms 3--7 were found to be neutral solvate, while in forms 1 and 2, proton transfer was observed from carboxylic acid to mebendazole.
文摘The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex
基金partial financial support from the Ministry of Science and Technology of China(No.2016YFE0132600)Zhengzhou University。
文摘A selective ring-opening [3+2] cyclization reaction of benzo[d]isoxazoles with 2-bromo-propanamides has been developed.The azaoxyallyl cation intermediates are employed as C^O 3-atom synthon to build oxa-heterocycles via the selectivity of suitable cyclization partners.This transformation provides rapid access to highly functionalized 2-hydroxyaryl-oxazolines under mild conditions and excellent regioselectivity.
基金We gratefully acknowledge the financial support from the Start-up Grant in Nanjing Tech University(Nos.39837118,39837146)the National Natural Science Foundation of China(No.22001121).
文摘This highlight summarizes a recent development of KF-promoted three-component fluorinationaminocarbonylation reaction of aldehydes,tertiary amines,and TMSCF_(2)Br for the synthesis of structurally importantα-fluoroamide derivatives.The key to the success of this method could be attributed to the multiple functions of difluorocarbene precursor(TMSCF_(2)Br)as both a C1 synthon and a F1 reagent through the process of C-F bond cleavage and C-F bond re-formation.