Pentafluorophenyl diphenylphosphate was found to be a novel convenient coupling reagent for the peptide synthesis with several advantages.Higher yield and lower racemization were found with this reagent than DCCI.
Lycorine and galantamine are natural alkaloids found in Amaryllidaceae plants, such as narcissus. Narcissus leaves and roots are sometimes accidentally ingested because they resemble vegetables. Lycorine and galantami...Lycorine and galantamine are natural alkaloids found in Amaryllidaceae plants, such as narcissus. Narcissus leaves and roots are sometimes accidentally ingested because they resemble vegetables. Lycorine and galantamine are toxic and cause such effects as nausea, vomiting, and abdominal pain, when accidentally ingested. In a case of narcissus poisoning, the detection of lycorine and galantamine in biological samples is vital to determine whether they have been ingested. This study establishes a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to measure the lycorine and galantamine content of human serum, which can be used for mild to fatal poisoning cases. A serum pretreatment procedure was performed using acetonitrile and QuEChERS AOAC powder. The separation of the compounds was conducted using a pentafluorophenyl column, CAPCELL CORE PFP (2.1 mm I.D. × 100 mm, 2.7 μm). Lycorine, galantamine, and galantamine-d<sub>6</sub> (internal standard) were identified by the transitions of m/z 288 → 147, m/z 288 → 213, and m/z 294 → 216, respectively. The calibration curves were linear in the ranges of 0.05 to 5 ng/mL and 5 to 100 ng/mL, with R<sup>2</sup> > 0.999. The precision and accuracy were within the permissible range. The matrix effects of lycorine and galantamine were 94.3% - 98.4% and 87.8% - 91.1%, respectively. The extraction recovery rates of lycorine and galantamine were 101.9% - 112.7% and 95.6% - 107.1%, respectively. The present method detected lycorine and galantamine in the sera of three patients with mild poisoning that had accidentally ingested. This method is applicable in cases of lycorine and galantamine poisoning.展开更多
Alkaloids are nitrogen-containing organic compounds, generally basic, and found in plants, fungi, and bacteria. Some alkaloids are used in medicine, but some compounds are highly toxic. Accidental ingestion, homicide,...Alkaloids are nitrogen-containing organic compounds, generally basic, and found in plants, fungi, and bacteria. Some alkaloids are used in medicine, but some compounds are highly toxic. Accidental ingestion, homicide, and suicide have occurred due to plants containing alkaloids. The identification of toxic components in biological samples is important for the diagnosis and/or treatment of poisoning cases in forensic and emergency medicine. Alkaloids have a wide variety of structures, such as isoquinoline alkaloid, indole alkaloid, tropane alkaloid, and diterpene alkaloid;therefore, there are few reports of simultaneous analysis methods. We have established a method for the simultaneous analysis of 23 alkaloids in human serum with a liquid chromatograph-tandem mass spectrometer (LC/MS/MS). A liquid-liquid extraction which was modified from the first step of the QuEChERS AOAC method was used for serum pretreatment. The separation of the compounds was performed using a pentafluorophenyl (PFP) column, CAPCELL CORE PFP (2.1 mm I.D. × 100 mm, 2.7 μm) in gradient mode. Mobile phase A consisted of 10 mM ammonium formate and 0.1% formic acid in ultrapure water, and mobile phase B was 10 mM ammonium formate and 0.1% formic acid in methanol. Simultaneous analysis was performed in dynamic multiple reaction monitoring mode. The separation of 23 alkaloids was satisfactory, as PFP columns exhibited different retention behaviors than alkyl phase columns. The PFP column effectively retained polar aromatic compounds;therefore, it was suitable for alkaloid analysis. The validated method was applied to a forensic case of aconite poisoning. The present method was useful in LC/MS/MS screening for 23 alkaloids in human serum.展开更多
A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first identified.Bis(pentafluorophenyl)(phenoxy)borane was used as a cat...A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first identified.Bis(pentafluorophenyl)(phenoxy)borane was used as a catalyst for the polymerization reaction system.And polytetrahydrofuran with high molecular weight and narrow molecular weight distribution could be obtained.The proposed mechanism was studied by MALDI-TOF,ESI-MS and O-18 isotope labeling analyses as a metal-free coordination insertion mechanism.展开更多
Introduction of substituents to organic radical is important to increase the stability and realize its applications as multifunctional materials.In this work,pentafluorophenyl group was introduced to 6-position of oly...Introduction of substituents to organic radical is important to increase the stability and realize its applications as multifunctional materials.In this work,pentafluorophenyl group was introduced to 6-position of olympicenyl radical(OR)via a newly designed synthetic strategy to afford the fourth OR derivative,OR4.Due to the combined electro-withdrawing effect and steric hindrance of pentafluorophenyl,OR4 was stable and isolable in crystalline state.展开更多
Comparison of the reaction speed and yield with its analogues and some conventional peptide coupling reagents, pentafluorophenyl diphenylphosphate (FDP) was shown to be a more preferable ''active ester'...Comparison of the reaction speed and yield with its analogues and some conventional peptide coupling reagents, pentafluorophenyl diphenylphosphate (FDP) was shown to be a more preferable ''active ester'' type reagent for the peptide synthesis. The synthesis of oligopeptides using FDP was achieved with high yields. The influences of several reaction parameters such as solvent, base, additive and temperature on the coupling reaction were studied using HPLC method. The degree of racemization with FDP determined by HPLC or Young test was shown to be lower than that of DCCI. Octapeptide Gly-Cys(Bzl)-Ser-Gly-Lys-Leu-Ile-Cys(Bzl)-OH, corresponding to the amino acid sequence of gp41 of HIV-1, was successfully synthesized by 5+3 approach using FDP with high yield.展开更多
Copolymers of N-pentafluorophenyl maleimide (PFPMI) with methyl methacrylate (MMA) were synthesized by a free radical initiator, such as AIBN. The refractive indexes of the copolymers remained nearly constant (1.4970 ...Copolymers of N-pentafluorophenyl maleimide (PFPMI) with methyl methacrylate (MMA) were synthesized by a free radical initiator, such as AIBN. The refractive indexes of the copolymers remained nearly constant (1.4970 at 532 nm) regardless of the polymer composition. These copolymers also showed high thermal stability. The orientational and photoelastic birefringence of the copolymers obtained were measured. Since both of the orientational and photoelastic birefringences of PMMA are negative whereas poly(PFPMI) exhibits positive, thus we have obtained nearly zero orientational and photoelastic birefringence polymers when the ratios of MMA/PFPMI were 91.8/8.2 and 97.0/3.0 mol%, respectively. Based on the experimental data, the ratios of MMA/PFPMI for zero birefringence were determined to be 88.9/11.1 and 93.8/6.2 mol% for orientational and photoelastic birefringence, respectively. The Tgs of corresponding copolymers were estimated to be 128 and 122 ℃.展开更多
A simple and facile synthesis of 14-aryl and alkyl-14H-dibenzo[a,j]xanthenes and 1,8-dioxooctahydroxanthene derivatives has been successfully developed by treatment of β-naphthol or dimedone with aldehydes under mild...A simple and facile synthesis of 14-aryl and alkyl-14H-dibenzo[a,j]xanthenes and 1,8-dioxooctahydroxanthene derivatives has been successfully developed by treatment of β-naphthol or dimedone with aldehydes under mild conditions in the presence of a pentafluorophenyl ammonium triflate(PFPAT) organocatalyst.These catalytic condensation reactions represent green chemical processes and the PFPAT organocatalyst is air-stable,cost-effective,easy to handle,and easily removed from the reaction mixtures.展开更多
文摘Pentafluorophenyl diphenylphosphate was found to be a novel convenient coupling reagent for the peptide synthesis with several advantages.Higher yield and lower racemization were found with this reagent than DCCI.
文摘Lycorine and galantamine are natural alkaloids found in Amaryllidaceae plants, such as narcissus. Narcissus leaves and roots are sometimes accidentally ingested because they resemble vegetables. Lycorine and galantamine are toxic and cause such effects as nausea, vomiting, and abdominal pain, when accidentally ingested. In a case of narcissus poisoning, the detection of lycorine and galantamine in biological samples is vital to determine whether they have been ingested. This study establishes a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to measure the lycorine and galantamine content of human serum, which can be used for mild to fatal poisoning cases. A serum pretreatment procedure was performed using acetonitrile and QuEChERS AOAC powder. The separation of the compounds was conducted using a pentafluorophenyl column, CAPCELL CORE PFP (2.1 mm I.D. × 100 mm, 2.7 μm). Lycorine, galantamine, and galantamine-d<sub>6</sub> (internal standard) were identified by the transitions of m/z 288 → 147, m/z 288 → 213, and m/z 294 → 216, respectively. The calibration curves were linear in the ranges of 0.05 to 5 ng/mL and 5 to 100 ng/mL, with R<sup>2</sup> > 0.999. The precision and accuracy were within the permissible range. The matrix effects of lycorine and galantamine were 94.3% - 98.4% and 87.8% - 91.1%, respectively. The extraction recovery rates of lycorine and galantamine were 101.9% - 112.7% and 95.6% - 107.1%, respectively. The present method detected lycorine and galantamine in the sera of three patients with mild poisoning that had accidentally ingested. This method is applicable in cases of lycorine and galantamine poisoning.
文摘Alkaloids are nitrogen-containing organic compounds, generally basic, and found in plants, fungi, and bacteria. Some alkaloids are used in medicine, but some compounds are highly toxic. Accidental ingestion, homicide, and suicide have occurred due to plants containing alkaloids. The identification of toxic components in biological samples is important for the diagnosis and/or treatment of poisoning cases in forensic and emergency medicine. Alkaloids have a wide variety of structures, such as isoquinoline alkaloid, indole alkaloid, tropane alkaloid, and diterpene alkaloid;therefore, there are few reports of simultaneous analysis methods. We have established a method for the simultaneous analysis of 23 alkaloids in human serum with a liquid chromatograph-tandem mass spectrometer (LC/MS/MS). A liquid-liquid extraction which was modified from the first step of the QuEChERS AOAC method was used for serum pretreatment. The separation of the compounds was performed using a pentafluorophenyl (PFP) column, CAPCELL CORE PFP (2.1 mm I.D. × 100 mm, 2.7 μm) in gradient mode. Mobile phase A consisted of 10 mM ammonium formate and 0.1% formic acid in ultrapure water, and mobile phase B was 10 mM ammonium formate and 0.1% formic acid in methanol. Simultaneous analysis was performed in dynamic multiple reaction monitoring mode. The separation of 23 alkaloids was satisfactory, as PFP columns exhibited different retention behaviors than alkyl phase columns. The PFP column effectively retained polar aromatic compounds;therefore, it was suitable for alkaloid analysis. The validated method was applied to a forensic case of aconite poisoning. The present method was useful in LC/MS/MS screening for 23 alkaloids in human serum.
基金funded by the National Key R&D Program of China(No.2021YFA1501700)the Science and Technology Development Plan of Jilin Province(Nos.20230101042JC,20210201059GX)+2 种基金the National Natural Science Foundation of China,Basic Science Center Program(No.51988102)the National Natural Science Foundation of China(Nos.52203017,52073272 and 22293062)Bureau of International Cooperation Chinese Academy of Sciences(No.029GJHZ2023017MI)。
文摘A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first identified.Bis(pentafluorophenyl)(phenoxy)borane was used as a catalyst for the polymerization reaction system.And polytetrahydrofuran with high molecular weight and narrow molecular weight distribution could be obtained.The proposed mechanism was studied by MALDI-TOF,ESI-MS and O-18 isotope labeling analyses as a metal-free coordination insertion mechanism.
基金support from the National Natural Science Foundation of China(Grant Nos.22201206,22222110,21971187)the National Science Foundation Of Tianjin(19JCJQJC62700)+1 种基金the China Postdoctoral Science Foundation(2022M722358)the Haihe Laboratory of Sustainable Chemical Transformations.
文摘Introduction of substituents to organic radical is important to increase the stability and realize its applications as multifunctional materials.In this work,pentafluorophenyl group was introduced to 6-position of olympicenyl radical(OR)via a newly designed synthetic strategy to afford the fourth OR derivative,OR4.Due to the combined electro-withdrawing effect and steric hindrance of pentafluorophenyl,OR4 was stable and isolable in crystalline state.
基金supported by the National Natural Science Foundation of China and the State Key labortory of Bio-organic and Natural Products Chemistry.
文摘Comparison of the reaction speed and yield with its analogues and some conventional peptide coupling reagents, pentafluorophenyl diphenylphosphate (FDP) was shown to be a more preferable ''active ester'' type reagent for the peptide synthesis. The synthesis of oligopeptides using FDP was achieved with high yields. The influences of several reaction parameters such as solvent, base, additive and temperature on the coupling reaction were studied using HPLC method. The degree of racemization with FDP determined by HPLC or Young test was shown to be lower than that of DCCI. Octapeptide Gly-Cys(Bzl)-Ser-Gly-Lys-Leu-Ile-Cys(Bzl)-OH, corresponding to the amino acid sequence of gp41 of HIV-1, was successfully synthesized by 5+3 approach using FDP with high yield.
基金supported by the Japan Society for the Promotion of Science (JSPS) through its "Funding Program for World Leading Innovative R&D on Science and Technology (FIRST Program)"
文摘Copolymers of N-pentafluorophenyl maleimide (PFPMI) with methyl methacrylate (MMA) were synthesized by a free radical initiator, such as AIBN. The refractive indexes of the copolymers remained nearly constant (1.4970 at 532 nm) regardless of the polymer composition. These copolymers also showed high thermal stability. The orientational and photoelastic birefringence of the copolymers obtained were measured. Since both of the orientational and photoelastic birefringences of PMMA are negative whereas poly(PFPMI) exhibits positive, thus we have obtained nearly zero orientational and photoelastic birefringence polymers when the ratios of MMA/PFPMI were 91.8/8.2 and 97.0/3.0 mol%, respectively. Based on the experimental data, the ratios of MMA/PFPMI for zero birefringence were determined to be 88.9/11.1 and 93.8/6.2 mol% for orientational and photoelastic birefringence, respectively. The Tgs of corresponding copolymers were estimated to be 128 and 122 ℃.
基金supported by the Islamic Azad University,Ayatollah Amoli Branch
文摘A simple and facile synthesis of 14-aryl and alkyl-14H-dibenzo[a,j]xanthenes and 1,8-dioxooctahydroxanthene derivatives has been successfully developed by treatment of β-naphthol or dimedone with aldehydes under mild conditions in the presence of a pentafluorophenyl ammonium triflate(PFPAT) organocatalyst.These catalytic condensation reactions represent green chemical processes and the PFPAT organocatalyst is air-stable,cost-effective,easy to handle,and easily removed from the reaction mixtures.
