Aminoalcohol

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Ruobing Chao - One of the best experts on this subject based on the ideXlab platform.

  • fragmentation study of Aminoalcohol diterpenoid alkaloids by electrospray ionization time of flight mass spectrometry
    Rapid Communications in Mass Spectrometry, 2016
    Co-Authors: Minghai Tang, Lu Wang, Ruobing Chao
    Abstract:

    Rationale Aminoalcohol-diterpenoid alkaloids were found to be a group of cardioactive substances in the lateral roots of Aconitum carmichaeli Debx. Studies on the fragmentation behaviors and features of these alkaloids in mass spectrometry would be important for their structural identification and in vivo metabolic research, which has not received much attention thus far. Methods In this study, the fragmentation behaviors of 14 Aminoalcohol-diterpenoid alkaloids were investigated by utilizing high-resolution time-of-flight tandem mass spectrometry. By analysis of the obtained MS2 data, we summarized the fragmentation features of the corresponding alkaloids under different collision energy. Results The dissociation of functional groups from the skeleton was observed as the main fragmentation way in electrospray ionization (ESI) mode. The order of fragmentation sites was C1/C3 > C16 > C15 > C6 > N, with loss of one or more CH3OH, H2O, C2H4 (substituent on N atom) or CO (at C15) groups. Conclusions The first systematic investigations on the fragmentation of Aminoalcohol-diterpenoid alkaloids are described in this paper, setting the stage for an in-depth identification and study of the corresponding components in complex systems. Copyright © 2015 John Wiley & Sons, Ltd.

  • simultaneous determination of thirteen Aminoalcohol diterpenoid alkaloids in the lateral roots of aconitum carmichaeli by solid phase extraction liquid chromatography tandem mass spectrometry
    Planta Medica, 2014
    Co-Authors: Jiayu Ding, Dongmei Xiong, Liming Ye, Ruobing Chao
    Abstract:

    Aminoalcohol-diterpenoid alkaloids have been reported as the cardioactive components in the lateral roots of Aconitum carmichaeli (Fuzi) according to recent studies. Determination of these effective components is of great significance for quality control purposes for Fuzi. Here we report, for the first, the development and validation of a new method to determine the 13 Aminoalcohol-diterpenoid alkaloids in Fuzi by using a simple and accurate solid-phase extraction-liquid chromatography-tandem mass spectrometry. The chromatographic analysis was performed on an ODS column with methanol-0.1 % formic acid (80 : 20, v/v) as the mobile phase. The quantification was performed using MS/MS detection in the positive ion mode with multiple reaction monitoring. Linearity was observed within a range of concentrations of 20–2000 ng/mL. For all the analytes, the r value was greater than 0.9990. The limit of detection and the limit of quantitation were less than 0.5 ng/mL and 2.0 ng/mL, respectively. The intraday and interday precisions were less than 5 % and 10 %, respectively. The accuracy was within the range of 90 to 105 %. This method was successfully applied to determine the 13 Aminoalcohol-diterpenoid alkaloids in Fuzi from different origins and with different processing methods.

Sakayu Shimizu - One of the best experts on this subject based on the ideXlab platform.

  • directed evolution of an Aminoalcohol dehydrogenase for efficient production of double chiral Aminoalcohols
    Journal of Bioscience and Bioengineering, 2011
    Co-Authors: Nobuyuki Urano, Michihiko Kataoka, Takeru Ishige, Shinji Kita, Keiji Sakamoto, Satoko Fukui, Shoko Kumashiro, Sakayu Shimizu
    Abstract:

    Abstract The Aminoalcohol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154, which can be used as a catalyst for the stereoselective reduction of ( S )-1-phenyl-1-keto-2-methylaminopropane to d -pseudoephedrine (dPE), is inhibited by the accumulation of dPE in the reaction mixture, limiting the yield of dPE. To improve this weak point of the enzyme, random mutations were introduced into aadh , and a mutant enzyme library was constructed. The mutant library was screened with a color detectable high-throughput screening method to obtain the evolved enzymes showing the activity in the presence of a high concentration of dPE. Two mutant enzymes showed higher tolerability to dPE than the wild type enzyme. Each of these enzymes had a single amino acid substitution in a different position (G73S and S214R), and a third mutant enzyme carrying both of these amino acid substitutions was constructed. Escherichia coli transformant cells, which express mutant AADHs, showed activity in the presence of 100 mg/ml dPE. A kinetic parameter analysis of the wild type and mutant enzymes was carried out. As compared with the wild type enzyme, the mutant enzymes carrying the S214R amino acid substitution or both the S214R and G73S substitutions showed higher k cat values, and the mutant enzymes carrying the G73S amino acid substitution or both the G73S and S214R substitutions showed higher K m values. These results suggest that the Ser214 residue plays an important role in enzyme activity, and that the Gly73 residue participates in enzyme–substrate binding.

  • genetic analysis around Aminoalcohol dehydrogenase gene of rhodococcus erythropolis mak154 a putative gntr transcription factor in transcriptional regulation
    Applied Microbiology and Biotechnology, 2011
    Co-Authors: Nobuyuki Urano, Michihiko Kataoka, Takeru Ishige, Shinji Kita, Keiji Sakamoto, Sakayu Shimizu
    Abstract:

    NADP+-dependent Aminoalcohol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154 catalyzes the reduction of (S)-1-phenyl-1-keto-2-methylaminopropane ((S)-MAK) to d-pseudoephedrine, which is used as a pharmaceutical. AADH is suggested to participate in Aminoalcohol or aminoketone metabolism in this organism because it is induced by the addition of several Aminoalcohols, such as 1-amino-2-propanol. Genetic analysis of around the aadh gene showed that some open reading frames (ORFs) are involved in this metabolic pathway. Four of these ORFs might form a carboxysome-like polyhedral organelle, and others are predicted to encode aminotransferase, aldehyde dehydrogenase, phosphotransferase, and regulator protein. OrfE, a homologous ORF of the FadR subfamily of GntR transcriptional regulators, lies downstream from aadh. To investigate whether or not orfE plays a role in the regulation of aadh expression, the gene disruption mutant of R. erythropolis MAK154 was constructed. The ΔorfE strain showed higher AADH activity than wild-type strain. In addition, a transformed strain, which harbored multi-orfE, showed no AADH activity even in the induced condition with 1-amino-2-propanol. These results suggest that OrfE is a negative regulator that represses aadh expression in the absence of 1-amino-2-propanol.

Arturo San Feliciano - One of the best experts on this subject based on the ideXlab platform.

  • long chain Aminoalcohol and diamine derivatives induce apoptosis through a caspase 3 dependent pathway
    Bioorganic & Medicinal Chemistry Letters, 2002
    Co-Authors: Esther Del Olmo, Mario Alves, Jose Luis Lopez, Antonio Macho, Fadwa El Banoua, Eduardo Munoz, Arturo San Feliciano
    Abstract:

    Abstract A number of long chain diamines and Aminoalcohols and several of their alkyl, acyl and carbamoyl derivatives, have been synthesized and evaluated for their apoptotic activities using the Jurkat cell line. Apoptosis was measured by flow cytometry and the best results were found for the Aminoalcohols displaying either a free alcohol or an amine with at least, one free hydrogen atom. The apoptotic pathway was mediated by a disruption of the mitochondria transmembrane potential and caspase-3 activation, inducing DNA fragmentation at the phase G 1 /S of the cell cycle.

  • synthesis and enzyme inhibitory activities of a series of lipidic diamine and Aminoalcohol derivatives on cytosolic and secretory phospholipases a2
    Bioorganic & Medicinal Chemistry Letters, 2000
    Co-Authors: Rut Lucas, Esther Del Olmo, Amalia Ubeda, Miguel Paya, Mario Alves, Jose Luis Lopez, Arturo San Feliciano
    Abstract:

    Abstract We have synthesised some lipidic diamines and Aminoalcohols and examined their behaviour as inhibitors of secretory and cytosolic PLA 2 . Some structure–activity relationships considerations have been deduced. Compound 14 Download high-res image (162KB) Download full-size image Scheme 1 . Synthesis of lipidic diamine and Aminoalcohol derivatives. i: a) EtOOCCl/N-methylmorpholine/THF; b) NaBH 4 /MeOH. ii) MsCl/Et 3 N/CH 2 Cl 2 . iii. NaN 3 /DMF. iv. Pd-C/HCCl 3 , NaBH 4 /MeOH. v: EtBr (or EtOOCCH 2 Br)/Et 3 N/DMF. vi: glutaric anhydride/EtOAc. vii: HCl/THF, Argon. viii: BnCl/NaH/DMF. ix: EtBr (1.2 or 2.2 eq.)/Et 3 N/DMF. x: succinic (maleic, glutaric) anh./EtOAc. xi: EtOOCCH 2 Br/Et 3 N. xii: H 2 /Pd-C/AcOH. xiii: 10% KOH/MmeOH. xiv: n -C 6 H 13 COCl ( n -C 15 H 31 COCl)/Et 2 O. xv: TMSCl/PhOH/HCCl 3 . was a potent and selective inhibitor of cPLA 2 and compound 4 showed a dual inhibitory profile against both types of PLA 2 while no cytotoxicity at 10 μM on human neutrophils or on murine macrophage line was observed for both.

Vladimir Dimitrov - One of the best experts on this subject based on the ideXlab platform.

  • Antimycobacterial activity of chiral Aminoalcohols with camphane scaffold
    European Journal of Medicinal Chemistry, 2014
    Co-Authors: Zhanina Petkova, Vladimir Dimitrov, Violeta Valcheva, Georgi Momekov, Petar Petrov, Irini A. Doytchinova, Georgi Stavrakov, Malinka Stoyanova
    Abstract:

    Abstract A series of Aminoalcohols were synthesized by reaction of aminolysis of camphor derived oxiranes with chosen amines. The compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis H37Rv. Ten of the new structures show much higher activity than the classical anti-TB drug ethambutol. Some of the most active compounds were tested against MDR strain 43, and four of them demonstrated excellent activities with MICs 0.27–0.72 μM. The cytotoxicity of representative exerting antimycobacterial activity compounds was assessed. Quantitative structure–activity relationship (QSAR) model is derived to estimate the contribution of each structural fragment to the activity. The camphane-based Aminoalcohols are promising lead compounds for further development of novel antimycobacterial agents.

  • Highly efficient synthesis of chiral Aminoalcohols and aminodiols with camphane skeleton
    Tetrahedron-asymmetry, 2013
    Co-Authors: Malinka Stoyanova, Boris Shivachev, Rosica P. Nikolova, Vladimir Dimitrov
    Abstract:

    Abstract Methylidene substituted camphor was easily epoxidized to give bridgehead oxirane-substituted camphor in the form of two diastereoisomers, isolated in pure form. These were used in aminolysis reactions with different secondary amines leading to series of chiral Aminoalcohols bearing a ketone functionality. The latter could be reduced by using LAH or DIBAL to a series of aminodiols. For the determination of the configuration of the newly formed stereogenic centre, advanced NMR experiments and X-ray crystallography were used. The new Aminoalcohols and aminodiols were tested as pre-catalysts for the enantioselective addition of Et2Zn to benzaldehyde showing moderate enantioselectivity.

  • Chiral β- and γ-Aminoalcohols derived from (+)-camphor and (−)-fenchone as catalysts for the enantioselective addition of diethylzinc to benzaldehyde
    Tetrahedron-asymmetry, 2001
    Co-Authors: Vladimir Dimitrov, Georgi M. Dobrikov, Miroslav Genov
    Abstract:

    Abstract The addition of Me 3 SiCN and LiCH 2 CN to (+)-camphor and (−)-fenchone, respectively, followed by reduction leads to chiral β- and γ-Aminoalcohols. The enantioselectivities realized using these Aminoalcohols as ligands in the addition of Et 2 Zn to benzaldehyde were lower than those obtained using the corresponding δ-Aminoalcohols.

  • Chiral Aminoalcohols with a menthane skeleton as catalysts for the enantioselective addition of diethylzinc to benzaldehyde
    Tetrahedron-asymmetry, 2001
    Co-Authors: Stefan Panev, Anthony Linden, Vladimir Dimitrov
    Abstract:

    Abstract Novel chiral Aminoalcohols were synthesized by highly diastereoselective addition of Me3SiCN and LiCH2CN to (−)-menthone followed by LiAlH4 reduction. The addition of CH2CH-MgBr and PhCHCH-MgBr to menthone and the following epoxidation, provided useful hydroxy epoxides, one of which could be aminolyzed to afford an aminodiol. In one case, the configuration of the newly formed epoxidic stereogenic center was determined by X-ray crystallography. When applied as catalysts in the enantioselective addition of Et2Zn to benzaldehyde, the Aminoalcohols induced enantiomeric excesses (e.e.s) of up to 77%.

  • new δ Aminoalcohol for the enantioselective addition of dialkylzincs to aldehydes
    Tetrahedron-asymmetry, 1997
    Co-Authors: Miroslav Genov, Vladimir Dimitrov, Valentina Ivanova
    Abstract:

    Abstract A new optically active δ-Aminoalcohol has been synthesized diastereoselectively in one step from (−)-menthone and N,N-dimethylaminopropyl lithium. The Aminoalcohol catalyzed the addition of diethylzinc and dimethylzinc to aldehydes in high yields and enantioselectivities of up to 89%.

Antonio Guarna - One of the best experts on this subject based on the ideXlab platform.