The Determination of Serne by the Use of Hantzsch Reaction

Abstract

A simple procedure for the determination of serine is described. The method involves the oxidation of serine to formaldehyde by periodate. The formaldehyde is then converted to 3,5-diacetyl - 1,4-dihydrolutidine by Hantzsch reaction in which acetyl acetone and ammonia are the reactants. The reaction product in low ranges (concentration of serine from 0.1 to 4 μg) is measured fluorometrically. In samples containing serine at concentrations higher than 4 μg colorimetric analysis is used. Recovery studies of serine added to washed mitochondrial preparations have been satisfactory. From the standpoint of sensitivity, simplicity and time required, this technique is an improvement over previously described procedures for serine determination.     

An improved synthesis of Fmoc-N-methyl serine and threonine

An improved method for the synthesis of Fmoc-N-methyl serine and threonine has been developed, which involves formation and subsequent reduction of the corresponding oxazolidinone with a Lewis acid under mild conditions, with improved yields and shorter reaction times.     

用微分脉冲伏安法测定铅(Ⅱ)-精氨酸及铅(Ⅱ)-丝氨酸络合物稳定常数

本文介绍了用微分脉冲伏安法以悬汞电极为工作电极测定铅(Ⅱ)-精氨酸及铅(Ⅱ)-丝氨酸络合物稳定常数。研究了仪器参数及实验条件对测定的影响,在20℃、离子强度为0.50M NaNO_3介质条件下,测得了铅(Ⅱ)-精氨酸及铅(Ⅱ)-丝氨酸络合物的累积稳定常数。     

Pt(II) stereoisomeric complexes with serine

There have been synthesized Pt(II) stereoisomeric complexes with hydroxy-α-amino acid serine (SerH = NH₂CH(CH₂OH)COOH is α-amino-β-hydroxypropionic acid): trans-[Pt(S-SerH)₂Cl₂], trans-[Pt(R-SerH)(S-SerH)Cl₂] with monodentately (through NH₂ group ) bound SerH and cis-, trans-[Pt(R-Ser)(S-Ser)], trans-[Pt(S-Ser)₂] with bidentately bound (through groups NH₂ and COO) ligands (R, S is the absolute configuration of asymmetric carbon atom). The successive phases in the synthesis of Pt(II) stereoisomeric complexes with serine were studied by ¹⁹⁵Pt NMR spectroscopy. To identificate the compounds synthesized the method of elemental analysis, IR and NMR (¹⁹⁵Pt, ¹³C, ¹H) spectroscopy were used. For trans-[Pt(R-Ser)(S-Ser)] the X-ray diffraction data were obtained.     

Taguchi Optimization for Combustion Synthesis of Aluminum Oxide Nano-particles

Nano-structured aluminum oxide powders were prepared by a combustion synthesis method utilizing serine as a new fuel. The product was sonicated to obtain nano powders. A Taguchi L-4 statistical design of combustion synthesis was utilized to optimize the production of γ-alumina powder. The product was characterized by XRD, BET, SEM, EDX and LLS. Nano crystalline γ-alumina with crystal sizes between 4.26 and 5.47 nm and α-Al2O3 powders with crystal sizes 24.51 and 28.62 nm were obtained by the combustion synthesis. The specific surface area was measured by a BET method to be 75.21 m2/g. The average particle size after sonication of product, observed by LLS, was 79.32 nm.     

N-（O,O-二异丙基）磷酰化丝氨酸成肽反应的立体效应研究

研究了N－（O,O－二异丙基）磷酰化－L－（或D－）丝氨酸和L－（或D－）组氨酸在水溶液中的反应及其与L－（或D－）组氨酸甲酯在DMSO中的反应,用SDS作对离子试剂,采用离子对反相高效液相色谱方法及反应产物进行分析。结果表明,所有反应体系中均有丝组二肽生成,而L－L和D－D型丝组二肽的生成量约是L－D和D－L型产物的4倍。     

铜锌超氧化物歧化酶与丝氨酸钴(Ⅱ)的相互作用

The effect of changing the amount of externally added cobalt(Ⅱ) serine, an organic metal compound, and the pH value of the enzyme solution on the interaction of copper zinc superoxide dismutase (Cu 2Zn 2SOD) with cobalt(Ⅱ) serine was studied by means of visible spectroscopy, inductively coupled plasma atomic emission spectrometry and measurement of enzyme activity. It was found that in aqueous solution, there exists a direct interaction of the metal ions of the active center in Cu 2Zn 2SOD with cobalt(Ⅱ) serine. As a result, part of the metal ions in the metalloenzyme were replaced by Co ion to form Co(Ⅱ) substituted derivatives of SOD and the catalytic activity of the enzyme decreased.     

Simultaneous determination of serine enantiomers in plasma using Mosher's reagent and stable isotope dilution gas chromatography-mass spectrometry

D-Serine is a co-agonist of the N-methyl-D-aspartate receptor in glutamate neurotransmission and has been proposed as a potential therapeutic agent for schizophrenia. However, D-serine also acts as a nephrotoxic substance in rats at high doses. To investigate the pharmacokinetics and toxicokinetics of D-serine, a method for the stereoselective determination of serine enantiomers in rat plasma was developed using GC-MS with selected ion monitoring (GC-MS-SIM). DL-[(2)H(3)]Serine was used as an internal standard to account for losses associated with the extraction, derivatization and chromatography. Serine enantiomers were purified by cation-exchange chromatography using BondElut SCX cartridge and derivatized with HCl in methanol to form methyl ester followed by subsequent N,O-diacylation with optically active (+)-α-methoxy-α-trifluoromethylphenylacetyl chloride to form epimeric amide. Quantitation was performed by SIM of the molecular-related ions of the epimers in the chemical ionization mode. The intra- and inter-day reproducibility of the assay was less than 5% for D-serine and 3% for L-serine. The method was successively applied to study the pharmacokinetics of D-serine in rats.