[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereoche...[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives.展开更多
To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elu...To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elucidated on the basis of extensive spectral data （IR, MS, 1 D- and 2D-NMR） analysis by comparing with literature data. A new cembranoid diterpene namely sarcophyolide A （1）, together with 7a, 8β-dihydroxydeepoxysarcophine （2） were isolated from this species. The cembranoid diterpenes with 7-1actone could be chemotaxonomic markers of Sarcophyton sp.展开更多
As a key contributor to memory storage, the synapse is one of the earliest affected neuronal components in Alzheimer＇s disease （AD）. Under physiological conditions, the synaptic con- nections between neurons underg...As a key contributor to memory storage, the synapse is one of the earliest affected neuronal components in Alzheimer＇s disease （AD）. Under physiological conditions, the synaptic con- nections between neurons undergo activity-dependent func- tional and morphological re-organisation. This dynamic, ＇plastic＇ neural ability critically depends on the structural integrity of the synapse. Thus, proteins that are implicated in preserving the organisation and dynamics of synaptic connections, including microtubules of the cytoskeleton and associated proteins, have attracted much focus for their involvement in the malfunction- ing AD synapse.展开更多
The structures of two novel lactams isolated from Clausena lansium were elucidated mainly on the bases of their spectral data. They are homoclausenamide(1),a -lactam,and zetaclausenamide(4), an eight-membered ring lac...The structures of two novel lactams isolated from Clausena lansium were elucidated mainly on the bases of their spectral data. They are homoclausenamide(1),a -lactam,and zetaclausenamide(4), an eight-membered ring lactam.展开更多
A novel and unusual sterol with unsaturation in the△^(5(14)) position,5α-cholesta-8(14),24(25)-diene-3β,6α-diol 1,was isolated from the South China Ses sponge Dysidea sp.The structure and relative stereochemistry ...A novel and unusual sterol with unsaturation in the△^(5(14)) position,5α-cholesta-8(14),24(25)-diene-3β,6α-diol 1,was isolated from the South China Ses sponge Dysidea sp.The structure and relative stereochemistry of 1 was established by spectral analysis and comparison to the spectral data of known sterols.展开更多
A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, I...A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis.展开更多
A new p-acetylphenyl glycoside,asterbatanoside A has been isolated from the roots of Aster batangensis, and its structure has been elucidated as p-hydroxyacetophenone- -O-α-D-xylopyranosyl-(1,6) -β-D-glucopyranosid...A new p-acetylphenyl glycoside,asterbatanoside A has been isolated from the roots of Aster batangensis, and its structure has been elucidated as p-hydroxyacetophenone- -O-α-D-xylopyranosyl-(1,6) -β-D-glucopyranoside by chemical and spectral means.For the confirmation of this structure. the synthesis of this compound was also reported in this paper.展开更多
On the basis of spectroscopic evidence (MS, ~1HNMR, ^(13)CNMR, CD, ~1H-~1H and ~1H-^(13)C cosy NMR) and chemical synthesis, the structure of isodopharicin E (1), isolated from the dry leaves and tender branches of Iso...On the basis of spectroscopic evidence (MS, ~1HNMR, ^(13)CNMR, CD, ~1H-~1H and ~1H-^(13)C cosy NMR) and chemical synthesis, the structure of isodopharicin E (1), isolated from the dry leaves and tender branches of Isodon pharicus (Prain) Murata was elucidated as 3R, 3'R, 13S, 13'S-tetrahydroxy-11S, 11'S-diacetoxy(16S-O-15')-bisentkaur-15'-en-15-one.展开更多
The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were ...The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were determined by degradation to be 3S4R.展开更多
The fruit of Camptotheca acuminate is used as a traditional Chinese medicine.Eight compounds were isolated from the fruit of Camptotheca acuminate for the first time,including(+)-(S)-abscisic acid(1),blumenol A(2),(E)...The fruit of Camptotheca acuminate is used as a traditional Chinese medicine.Eight compounds were isolated from the fruit of Camptotheca acuminate for the first time,including(+)-(S)-abscisic acid(1),blumenol A(2),(E)-3-hydroxymegastigm-7-en-9-one(3),(-)-(3R)-3,5-dimethyl-8-methoxy-3,4-dihydroisocoumarin(4),(-)-(3R)-8-methoxy-3-methyl-3,4-dihydro-1H-isochromen-1-one(5),neocnidilide(6),(3S)-butylphthalide(7)and senkyunolide I(8).Their structures were determined by comprehensive spectroscopic methods,including HRESIMS and 1D NMR.展开更多
AM1 method was emyloyed to calculate flavonoid antioxidants, and the results obtained are as follows. Firstly, flavonoid hydroxyls atortho position were more active than the hydroxyls atmeta position in scavenging oxy...AM1 method was emyloyed to calculate flavonoid antioxidants, and the results obtained are as follows. Firstly, flavonoid hydroxyls atortho position were more active than the hydroxyls atmeta position in scavenging oxygen-free raidicals, which resulted from the facts that (i) the former were stabilized by forming intramolecular hydrogen bond and (ii)ortho benzocluinone formed in the former structures through resonance, which resulted in large percentage of distribution of spin density or1ortho oxygen and low internal energy. Secondly, electron-attracting effect of ring C of chromone-flavonoids showed some passive efftrts on hydroxyls of ring A, making the OH less active. As ring C had little effect on ring B and hydroxyls of ring B in most flavonoids were atortho position, the rule summarized from experiments showing that hydroxyls of ring B were more active in scavenging oxygen-free radicals was elucidated.展开更多
Nine bisabolangelone reduction derivatives were synthesized and separated as potential anti-ulcer agent. Their structures were characterized by 2D NMR, IR, ESI-MS, elemental analysis and single-crystal X-ray diffracti...Nine bisabolangelone reduction derivatives were synthesized and separated as potential anti-ulcer agent. Their structures were characterized by 2D NMR, IR, ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis. Preliminarily H＋/K＋-ATPase activity evaluation indicated that all the target compounds had a certain inhibitory effect, and compounds Ⅱ and IV exhibited the better inhibitory activity against H＋/K＋-ATPase than bisabolangelone and the commercial omeprazole with the IC50 of 23.21 and 65.32 pmol/L, respectively. The initial structure-activity analysis suggested that the presence of carbonyl group in six-membered ring and double bond in side-chain seemed to be necessary to the activity.展开更多
An expert system for the elucidation of the structures of organic compounds--ESESOC-IIhas been designed. It is composed of three parts: spectroscopic data analysis, structure generator, and evaluation of the candidate...An expert system for the elucidation of the structures of organic compounds--ESESOC-IIhas been designed. It is composed of three parts: spectroscopic data analysis, structure generator, and evaluation of the candidate structures. The heart of ESESOC is the structure generator, as an integral part, which accepts the specific types of information, e.g. molecular formulae, substructure constraints, and produces an exhaustive and irredundant list of candidate structures. The scheme for the structural generation is given, in which the depth-first search strategy is used to fill the bonding adjacency matrix (BAM) and a new method is introduced to remove the duplicates.展开更多
A series of spiro compounds have been synthesized via several steps. The structure of these compounds were confirmed by ^1H NMR, 13C NMR, IR, MS spectra and X-ray diffraction analysis. The possible mechanism to form t...A series of spiro compounds have been synthesized via several steps. The structure of these compounds were confirmed by ^1H NMR, 13C NMR, IR, MS spectra and X-ray diffraction analysis. The possible mechanism to form these products was also proposed.展开更多
Euphorstranoids A(1)and B(2),two highly rearranged ingenane diterpenoids with an unusual 5/6/7/3 carbon ring system,were isolated from Euphorbia stracheyi.Their structures were determined by a combination of spectral,...Euphorstranoids A(1)and B(2),two highly rearranged ingenane diterpenoids with an unusual 5/6/7/3 carbon ring system,were isolated from Euphorbia stracheyi.Their structures were determined by a combination of spectral,chemical,and X-ray diffraction methods.The plausible biosynthetic pathway of 1 and 2 was proposed and chemically mimicked.Compounds 1 and 2 significantly inhibited the triglyceride(TG)level in 3T3-L1 adipocytes via retarding cell adipogenesis at the early stage.展开更多
A new class of potent liver injury protective compounds,phychetins A-D(1-4)featuring an unique 6/6/5/6/5 pentacyclic framework,were isolated and structurally characterized from a Chinese medicinal plant Phyllanthus fr...A new class of potent liver injury protective compounds,phychetins A-D(1-4)featuring an unique 6/6/5/6/5 pentacyclic framework,were isolated and structurally characterized from a Chinese medicinal plant Phyllanthus franchetianus.Compounds 2-4 are three pairs of enantiomers that were initially obtained in a racemic manner,and were further separated by chiral HPLC preparation.Compounds 1-4 were proposed to be originated biosynthetically from a coexisting lignan via an intramolecular Friedel-Crafts reaction as the key step.A bioinspired total synthesis strategy was thus designated,and allowed the effective syntheses of compounds 2-4 in high yields.Some of compounds exhibited significant anti-inflammatory activities in vitro via suppressing the production of pro-inflammatory cytokine IL-1β.Notably,compound 4,the most active enantiomeric pair in vitro,displayed prominent potent protecting activity against liver injury at a low dose of 3 mg/kg in mice,which could serve as a promising lead for the development of acute liver injury therapeutic agent.展开更多
Common wheat(Triticum aestivum L.)is a leading cereal crop,but has lagged behind with respect to the interpretation of the molecular mechanisms of phenotypes compared with other major cereal crops such as rice and mai...Common wheat(Triticum aestivum L.)is a leading cereal crop,but has lagged behind with respect to the interpretation of the molecular mechanisms of phenotypes compared with other major cereal crops such as rice and maize.The recently available genome sequence of wheat affords the pre-requisite information for efficiently exploiting the potential molecular resources for decoding the genetic architecture of complex traits and identifying valuable breeding targets.Meanwhile,the successful application of metabolomics as an emergent large-scale profiling methodology in several species has demonstrated this approach to be accessible for reaching the above goals.One such productive avenue is combining metabolomics approaches with genetic designs.However,this trial is not as widespread as that for sequencing technologies,especially when the acquisition,understanding,and application of metabolic approaches in wheat populations remain more difficult and even arguably underutilized.In this review,we briefly introduce the techniques used in the acquisition of metabolomics data and their utility in large-scale identification of functional candidate genes.Considerable progress has been made in delivering improved varieties,suggesting that the inclusion of information concerning these metabolites and genes and metabolic pathways enables a more explicit understanding of phenotypic traits and,as such,this procedure could serve as an-omics-informed roadmap for executing similar improvement strategies in wheat and other species.展开更多
Structural elucidation (automatic determination of the structure of amolecule from its spectra) is frequently hampered by combinatorial explosion when trying to assemblethe identified substructures. We devised a new m...Structural elucidation (automatic determination of the structure of amolecule from its spectra) is frequently hampered by combinatorial explosion when trying to assemblethe identified substructures. We devised a new method which can avoid this pitfall by a systematicexamination of allowed ^(13)C chemical shifts ranges for all substructures chemically possible andcombined with a progressive pruning thanks to neighbouring relationships appearing from 2D NMR. Thismethod is explained by a detailed example.展开更多
Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type...Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.展开更多
基金supported by the National Key R&D Program of China(No.2023YFC3503902)the National Natural Science Foundation of China(Nos.82293681(82293680)and 82321004)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(Nos.2022B1515120015 and 2021A1515111021)the Guangdong Major Project of Basic and Applied Basic Research(No.2023B0303000026)the Science and Technology Projects in Guangzhou(No.202102070001).
文摘[2+2]-Type cyclobutane derivatives comprise a large family of natural products with diverse molecular architectures.However,the structure elucidation of the cyclobutane ring,including its connection mode and stereochemistry,presents a significant challenge.Plumerubradins A-C(1-3),three novel iridoid glycoside[2+2]dimers featuring a highly functionalized cyclobutane core and multiple stereogenic centers,were isolated from the flowers of Plumeria rubra.Through biomimetic semisynthesis and chemical degradation of compounds 1-3,synthesis of phenylpropanoid-derived[2+2]dimers 7-10,combined with extensive spectroscopic analysis,single-crystal X-ray crystallography,and microcrystal electron diffraction experiments,the structures with absolute configurations of 1-3 were unequivocally elucidated.Furthermore,quantum mechanics-based^(1)H NMR iterative full spin analysis successfully established the correlations between the signal patterns of cyclobutane protons and the structural information of the cyclobutane ring in phenylpropanoid-derived[2+2]dimers,providing a diagnostic tool for the rapid structural elucidation of[2+2]-type cyclobutane derivatives.
基金National Natural Science Foundation of China(Grant No.30672607)the National Hi-Tech Projects(Grant No.2006AA09Z446,2006DFA31100 and 2006AA09Z405)+1 种基金China Uni-PhD Base Project(Grant No.20060001149)International Cooperation Projects of BMBF-MOST.
文摘To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elucidated on the basis of extensive spectral data （IR, MS, 1 D- and 2D-NMR） analysis by comparing with literature data. A new cembranoid diterpene namely sarcophyolide A （1）, together with 7a, 8β-dihydroxydeepoxysarcophine （2） were isolated from this species. The cembranoid diterpenes with 7-1actone could be chemotaxonomic markers of Sarcophyton sp.
基金supported by grant SDU2020 to Prof.Bente Finsen and Prof.Martin R.Larsen(COPING AD–Collaborative Project on the Interaction between Neurons and Glia in Alzheimer’s Disease)
文摘As a key contributor to memory storage, the synapse is one of the earliest affected neuronal components in Alzheimer＇s disease （AD）. Under physiological conditions, the synaptic con- nections between neurons undergo activity-dependent func- tional and morphological re-organisation. This dynamic, ＇plastic＇ neural ability critically depends on the structural integrity of the synapse. Thus, proteins that are implicated in preserving the organisation and dynamics of synaptic connections, including microtubules of the cytoskeleton and associated proteins, have attracted much focus for their involvement in the malfunction- ing AD synapse.
文摘The structures of two novel lactams isolated from Clausena lansium were elucidated mainly on the bases of their spectral data. They are homoclausenamide(1),a -lactam,and zetaclausenamide(4), an eight-membered ring lactam.
文摘A novel and unusual sterol with unsaturation in the△^(5(14)) position,5α-cholesta-8(14),24(25)-diene-3β,6α-diol 1,was isolated from the South China Ses sponge Dysidea sp.The structure and relative stereochemistry of 1 was established by spectral analysis and comparison to the spectral data of known sterols.
文摘A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis.
文摘A new p-acetylphenyl glycoside,asterbatanoside A has been isolated from the roots of Aster batangensis, and its structure has been elucidated as p-hydroxyacetophenone- -O-α-D-xylopyranosyl-(1,6) -β-D-glucopyranoside by chemical and spectral means.For the confirmation of this structure. the synthesis of this compound was also reported in this paper.
文摘On the basis of spectroscopic evidence (MS, ~1HNMR, ^(13)CNMR, CD, ~1H-~1H and ~1H-^(13)C cosy NMR) and chemical synthesis, the structure of isodopharicin E (1), isolated from the dry leaves and tender branches of Isodon pharicus (Prain) Murata was elucidated as 3R, 3'R, 13S, 13'S-tetrahydroxy-11S, 11'S-diacetoxy(16S-O-15')-bisentkaur-15'-en-15-one.
文摘The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were determined by degradation to be 3S4R.
文摘The fruit of Camptotheca acuminate is used as a traditional Chinese medicine.Eight compounds were isolated from the fruit of Camptotheca acuminate for the first time,including(+)-(S)-abscisic acid(1),blumenol A(2),(E)-3-hydroxymegastigm-7-en-9-one(3),(-)-(3R)-3,5-dimethyl-8-methoxy-3,4-dihydroisocoumarin(4),(-)-(3R)-8-methoxy-3-methyl-3,4-dihydro-1H-isochromen-1-one(5),neocnidilide(6),(3S)-butylphthalide(7)and senkyunolide I(8).Their structures were determined by comprehensive spectroscopic methods,including HRESIMS and 1D NMR.
基金Project supported by the Doctoral Foundation of Science of Shandong Teachers University
文摘AM1 method was emyloyed to calculate flavonoid antioxidants, and the results obtained are as follows. Firstly, flavonoid hydroxyls atortho position were more active than the hydroxyls atmeta position in scavenging oxygen-free raidicals, which resulted from the facts that (i) the former were stabilized by forming intramolecular hydrogen bond and (ii)ortho benzocluinone formed in the former structures through resonance, which resulted in large percentage of distribution of spin density or1ortho oxygen and low internal energy. Secondly, electron-attracting effect of ring C of chromone-flavonoids showed some passive efftrts on hydroxyls of ring A, making the OH less active. As ring C had little effect on ring B and hydroxyls of ring B in most flavonoids were atortho position, the rule summarized from experiments showing that hydroxyls of ring B were more active in scavenging oxygen-free radicals was elucidated.
基金Project supported by the National Natural Science Foundation of China （No. 30970296）, the Scientific and Technological Research Project of Hubei Provincial Department of Education （No. Q20111210）, the Doctoral Startup Foundation of China Three Gorges University （No. KJ2009B046） and the Preresearch Foundation of College of Chemistry and Life Sciences （No. HY0905）.
文摘Nine bisabolangelone reduction derivatives were synthesized and separated as potential anti-ulcer agent. Their structures were characterized by 2D NMR, IR, ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis. Preliminarily H＋/K＋-ATPase activity evaluation indicated that all the target compounds had a certain inhibitory effect, and compounds Ⅱ and IV exhibited the better inhibitory activity against H＋/K＋-ATPase than bisabolangelone and the commercial omeprazole with the IC50 of 23.21 and 65.32 pmol/L, respectively. The initial structure-activity analysis suggested that the presence of carbonyl group in six-membered ring and double bond in side-chain seemed to be necessary to the activity.
基金Project supported by the Naional Natural Science Foundaion of China.
文摘An expert system for the elucidation of the structures of organic compounds--ESESOC-IIhas been designed. It is composed of three parts: spectroscopic data analysis, structure generator, and evaluation of the candidate structures. The heart of ESESOC is the structure generator, as an integral part, which accepts the specific types of information, e.g. molecular formulae, substructure constraints, and produces an exhaustive and irredundant list of candidate structures. The scheme for the structural generation is given, in which the depth-first search strategy is used to fill the bonding adjacency matrix (BAM) and a new method is introduced to remove the duplicates.
基金Project supported by the National Natural Science Foundation of China （No. 20472047）.
文摘A series of spiro compounds have been synthesized via several steps. The structure of these compounds were confirmed by ^1H NMR, 13C NMR, IR, MS spectra and X-ray diffraction analysis. The possible mechanism to form these products was also proposed.
基金This work was supported by the Natural Science Foundation of China(No.81973195,82104020,22167009 and 81973203)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Y093)+1 种基金the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.SML2021SP301)the Dongguan Social Science and Technology Development(Key)Project,China(No.202050715024223).
文摘Euphorstranoids A(1)and B(2),two highly rearranged ingenane diterpenoids with an unusual 5/6/7/3 carbon ring system,were isolated from Euphorbia stracheyi.Their structures were determined by a combination of spectral,chemical,and X-ray diffraction methods.The plausible biosynthetic pathway of 1 and 2 was proposed and chemically mimicked.Compounds 1 and 2 significantly inhibited the triglyceride(TG)level in 3T3-L1 adipocytes via retarding cell adipogenesis at the early stage.
基金Financial support from the National Natural Science Foundations of China(No.22237007,22177121 and 92057116)supported by the grants from Science and Technology Commission of Shanghai Municipality(No.20ZR1467800 and 19431908100,China)。
文摘A new class of potent liver injury protective compounds,phychetins A-D(1-4)featuring an unique 6/6/5/6/5 pentacyclic framework,were isolated and structurally characterized from a Chinese medicinal plant Phyllanthus franchetianus.Compounds 2-4 are three pairs of enantiomers that were initially obtained in a racemic manner,and were further separated by chiral HPLC preparation.Compounds 1-4 were proposed to be originated biosynthetically from a coexisting lignan via an intramolecular Friedel-Crafts reaction as the key step.A bioinspired total synthesis strategy was thus designated,and allowed the effective syntheses of compounds 2-4 in high yields.Some of compounds exhibited significant anti-inflammatory activities in vitro via suppressing the production of pro-inflammatory cytokine IL-1β.Notably,compound 4,the most active enantiomeric pair in vitro,displayed prominent potent protecting activity against liver injury at a low dose of 3 mg/kg in mice,which could serve as a promising lead for the development of acute liver injury therapeutic agent.
基金supported by the National Natural Science Foundation of China(91935304,31770328,and 32001541)the Huazhong Agricultural University Scientific&Technological Self-Innovation Foundation(2017RC006)+1 种基金the China Postdoctoral Science Foundation(2018M642866 and 2021T140246)the Hubei Provincial Natural Science Foundation(2020CFB149).
文摘Common wheat(Triticum aestivum L.)is a leading cereal crop,but has lagged behind with respect to the interpretation of the molecular mechanisms of phenotypes compared with other major cereal crops such as rice and maize.The recently available genome sequence of wheat affords the pre-requisite information for efficiently exploiting the potential molecular resources for decoding the genetic architecture of complex traits and identifying valuable breeding targets.Meanwhile,the successful application of metabolomics as an emergent large-scale profiling methodology in several species has demonstrated this approach to be accessible for reaching the above goals.One such productive avenue is combining metabolomics approaches with genetic designs.However,this trial is not as widespread as that for sequencing technologies,especially when the acquisition,understanding,and application of metabolic approaches in wheat populations remain more difficult and even arguably underutilized.In this review,we briefly introduce the techniques used in the acquisition of metabolomics data and their utility in large-scale identification of functional candidate genes.Considerable progress has been made in delivering improved varieties,suggesting that the inclusion of information concerning these metabolites and genes and metabolic pathways enables a more explicit understanding of phenotypic traits and,as such,this procedure could serve as an-omics-informed roadmap for executing similar improvement strategies in wheat and other species.
文摘Structural elucidation (automatic determination of the structure of amolecule from its spectra) is frequently hampered by combinatorial explosion when trying to assemblethe identified substructures. We devised a new method which can avoid this pitfall by a systematicexamination of allowed ^(13)C chemical shifts ranges for all substructures chemically possible andcombined with a progressive pruning thanks to neighbouring relationships appearing from 2D NMR. Thismethod is explained by a detailed example.
文摘Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.
