含四氢噻吩类生物素杂质的合成

d-生物素(d-Biotin)又称维生素H、辅酶R,其已广泛应用于医药、家禽、家畜的营养和饲料添加剂方面[1-4].目前比较权威的质量标准是欧洲药典[5],其在美国药典[6]的基础上提出了5个有关物质(杂质A,B,C,D,E)的TLC控制.     

阻抑动力学荧光法测定氨苄青霉素

氨苄青霉素属于β-内酰胺类抗生素,是国内临床上广泛使用的广谱青霉素,其含量测定多采用紫外可见分光光度法[1-2]、高效液相色谱法[3]、电位滴定法[4]、化学发光法[5]、极谱法[6]等。但上述方法有的试剂繁多操作复杂,有的费时,灵敏度不高,线性范围较窄。美国药典(第23版)采用剩     

罗红霉素的荷移分光光度法测定

罗红霉素为半合成的14元大环内酯类抗生素,对肺炎支原体、肺炎衣原体、溶脲脲原体也有抗菌活性,药典上记录的检测方法为抗生素微生物检定法[1],比较繁琐,费时较长。目前已报道的分析方法主要有HPLC法[2]、RHPLC法[3]、LC法[4]、SP法[5]、荷移反应[6]等。本文利用TCNQ与罗红霉素     

生物素-亲和素系统在压电免疫传感器中质量放大作用研究

生物素-亲和素系统(BiotinAvidinSystem,BAS)是70年代后期迅速发展起来的一种新型生物放大系统,具有高灵敏度、高特异性以及简便、经济、快速等优点,在现代生物免疫学领域中已得到广泛的应用^[1].     

生物素中间体内酯合成进展

简述了生物素合成方法,并综述了有关生物素中间体内酯(3aS,6aR)-1,3-二苄基一六氢-1H-呋喃并[3,4-d]咪唑-2,4-二酮的合成进展。     

基于有序生物膜的电容型层胶粘蛋白新型免疫传感器

免疫传感器以其高度特异性抗原抗体结合反应的特点 ,可直接、快速而灵敏地测定抗原或抗体分子而被广泛应用于临床医学以及环境污染物检测等领域 [1] .目前 ,检测抗原抗体结合的无标志方法主要有石英晶体微天平 [2 ] 、表面等离子共振 [3 ] 、界面电容 [4 ] 及原子力显微镜 [5]     

微波加热法测定灯盏花素的水分

药物中水分的测定一般是根据中国药典规定,在105℃控温烘箱中加热5h,称量至恒重,然后计算失去的水分[1].目前微波加热在化学领域已得到了广泛的应用,用微波加热对药物中水分的测定,已有报道[2,3].但是用微波加热测定灯盏花素中水分,与药典方法相比,微波法具有操作简便,快速,低耗能的优点.本法用微波加热法测定灯盏花素的水分含量,并与药典法进行比较,结果满意.     

顶空-气相色谱法测定水中2-乙基苯胺的含量

正2-乙基苯胺属苯胺类化合物,是重要的有机合成中间体[1],广泛应用于化工、印染和制药等领域,可通过吸入、食入或皮肤吸收等途径进入人体,导致人体中毒,造成人体血液循环系统损害,可直接作用于肝细胞,引起神经系统损害[2-3]。目前,水中2-乙基苯胺测定主要有分光光度法[4]、气相色谱法(GC)[5-6]和高效液相色谱法(HPLC)[7]等,样品前     

气相色谱法测定不对称催化合成反应液中手性1,1-二苯基-2-丙醇含量

(S)-(+)-1,1-二苯基-2-丙醇是一种很有用的医药中间体,用它可以合成生物素,此物质广泛应用于医学各领域。近年来大量研究证实,生物素-亲和素(BAS)系统几乎可与目前研究成功的各种标记物结合。在生物素-亲和素(BAS)系统中,借助所形成的生物素-亲和素-酶复合物,追踪生物素标记的抗原或抗体,通过酶催化底物显色,可检出相应的抗体或抗原。由于抗原或抗体分子可偶联多个生物素,     

激光拉曼光谱内标法直接测定甲醇含量

<正>激光拉曼光谱法作为一种新型无损检测技术,广泛应用于样品的定性、定量分析[1-3]。目前,样品中甲醇的定量分析方法常用的有气相色谱法[4]、分光光度法[5]和传感器法[6]等。本工作通过不同浓度的甲醇拉曼光谱特征峰(1 016.46cm-1)与乙醇的拉曼光谱特征峰(877.95cm-1)组成相对强度比,建立线性回归方程。本法具有测定简单、操作方便,无需添加其他化学试剂,可用于甲醇含量的直接检测。     

Synthesis of （3aS,6aR）- 1,3-Dibenzyl-tetrahydro- 1H-thieno[3,4-d]-imidazole-2（3H）-one-4-ylidenepentanoic Acid and Characterization of Its Crystal

1 INTRODUCTION The title compound, (3aS,6aR)-1.3-dibenzyl- tetrahydro-1H-thieno[3,4-d]-imidazole-2(3H)-one- 4-ylidenepentanoic acid 3, is a key intermediate for the synthesis of d-biotin 1 (VITH, Fig. 1) which has been widely used not only as a pharmaceu…     

替格瑞洛的合成工艺改进

以2-丙硫基-4,6-二氢-5-氨基嘧啶和2-{［(3aR,4S,6R,6aS)-6-氨基-2,2-二甲基四氢-3aH-环戊基［d］［1,3］二氧-4-基］氧}-1-乙醇L-酒石酸盐为原料,经C-N偶联,亲核取代和环合反应制得2-{［(3aR,4S,6R,6aS)-6-(7-氯-5-丙硫基-3H-［1,2,3］三唑［4,5-d］嘧啶-3-基)-2,2-二甲基四氢-3aH-环戊基［d］［1,3］二氧-4-基］氧}-1-乙醇(4); 4与(1R,2S)-2-(3,4-二氟苯基)环丙胺D-扁桃酸盐经亲核取代反应后酸解脱除丙酮叉保护基合成替格瑞洛,总收率58.7%,纯度99.2%,其结构经¹H NMR, MS(ESI)和XRD确证。     

A convergent approach to the marine natural product eleutherobin: synthesis of key intermediates and attempts to produce the basic skeleton

Synthesis of (1R,5R,6R)-2-(6-hydroxymethyl-5-isopropyl-2-methylcyclohex-2-enyl)-N- methoxy-N-methylacetamide 8 from R-(-)-phellandrene in six steps, and (3aR*,4S*,6R*,6aS*)- (6-hydroxymethyl-4-methoxy-2,2,6-trimethyltetrahydrofuro[3,4-d][1,3]dioxol- 4-yl)acetic acid methyl ester 17 from tetrabromoacetone and 2-methoxy-5-methylfuran in six steps, provided two key fragments which have been combined to produce intermediates for attempted construction of the basic skeleton of eleutherobin.     

Total synthesis of optically active lycopladine A by utilizing diastereoselective protection of carbonyl group in a 1,3-cyclohexanedione derivative

We successfully synthesized two enantiomers of bicyclic enones, (7R,7aR)- and (7S,7aS)-9, from the hemiacetal 2a, which we first synthesized from the symmetrical diketone 1a via diastereoselective carbon-oxygen bond formation between one of the carbonyl groups and the chiral alcohol on the C2 side chain in a 2,2-disubstituted 1,3-cycloalkanedione derivative. We also report the total synthesis of natural (+)-lycopladine A [(+)-6] from (7R,7aR)-9 and the formal synthesis of unnatural (-)-lycopladine A [(-)-6] from (7S,7aS)-9.     

Synthesis and pharmacological effects of the enantiomers of the N-phenethyl analogues of the ortho and para e- and f-oxide-bridged phenylmorphans

The N-phenethyl analogues of (1R*,4aR*,9aS*)-2-phenethyl-1,3,4,9a-tetrahydro-2H-1,4a-propanobenzofuro[2,3-c]pyridin-6-ol and 8-ol and (1R*,4aR*,9aR*)-2-phenethyl-1,3,4,9a-tetrahydro-2H-1,4a-propanobenzofuro[2.3-c]pyridin-6-ol and 8-ol, the ortho- (43) and para-hydroxy e- (20), and f-oxide-bridged 5-phenylmorphans (53 and 26) were prepared in racemic and enantiomerically pure forms from a common precursor, the quaternary salt 12. Optical resolutions were accomplished by salt formation with suitable enantiomerically pure chiral acids or by preparative HPLC on a chiral support. The N-phenethyl (-)- para-e enantiomer (1S,4aS,9aR-(-)-20) was found to be a mu-opioid agonist with morphine-like antinociceptive activity in a mouse assay. In contrast, the N-phenethyl (-)-ortho-f enantiomer (1R,4aR,9aR-(-)-53) had good affinity for the mu-opioid receptor (K(i) = 7 nM) and was found to be a mu-antagonist both in the [(35)S]GTP-gamma-S assay and in vivo. The molecular structures of these rigid enantiomers were energy minimized with density functional theory at the level B3LYP/6-31G* level, and then overlaid on a known potent mu-agonist. This superposition study suggests that the agonist activity of the oxide-bridged 5-phenylmorphans can be attributed to formation of a seven membered ring that is hypothesized to facilitate a proton transfer from the protonated nitrogen to a proton acceptor in the mu-opioid receptor.     

Chemoenzymatic synthesis of (+)-alpha-polypodatetraene and methyl (5R,10R,13R)-labda-8-en-15-oate

The reported enzymatic resolution products {acetate of (1S,4aS,8aS)-1,2,3,4,4a,5,6,7,8,8a-decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2-ethylene acetal} (8aS)-5 (>99% ee)] and [(1R,4aR,8aR)-1,2,3,4,4a,5,6,7,8,8a-decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2-ethylene acetal (8aR)-4 (98% ee) were converted to (+)-alpha-polypodatetraene (1) and methyl (5R,10R,13R)-labda-8-en-15-oate (2), respectively. For the synthesis of (5R,10R,13R)-2, chiral isoprene congener (3S)-26 corresponding to the right part of 2 was synthesized based on the lipase-assisted resolution of (+/-)-2-methyl-3- (p-methoxyphenyl)propanol (17).     

Synthesis of an optically active, bicyclic 2-pyridone dipeptide mimetic

The eleven-step preparation of the bicyclic 2-pyridone dipeptide mimetic 1 [(3S)-6-(benzyloxycarbonylamino)-5-oxo-1,2,3,5-tetrahydroindolizine-3-carboxylic acid] in optically active form (60% ee) is described. Key steps in the synthesis of 1 include the osmium-catalyzed asymmetric dihydroxylation of olefin 13 [(6-but-3-enyl-2-methoxypyridin-3-yl)carbamic acid benzyl ester] and the intramolecular cyclization of protected diol 19 [(3'R)-[6-[4'-(tert-butyldimethylsilanyloxy)-3'-hydroxybutyl]-2-methoxypyridin-3-yl]carbamic acid benzyl ester] to afford the pyridinium salt 20 [(3S)-[3-(tert-butyldimethylsilanyloxymethyl)-5-methoxy-2,3-dihydro-1H-indolizin-6-yl]carbamic acid benzyl ester trifuoromethanesulfonic acid salt]. Several alternate methods to prepare olefin 13 are also discussed.     

一种新型噁唑烷酮类抗生素的合成

以2,4-二溴吡啶为原料,经Weinreb酰胺酰化、Noyori不对称氢转移反应、脱Boc保护基、环化、Suzuki偶联、磷酸单酯化及成盐共七步反应制得一种新型噁唑烷酮类抗生素【【(3R,3aS)-7-{6-［(S)3-甲基-2-噁唑烷酮-5-基］吡啶-3-基}-1-氧-1,3,3a,4-四氢苯并［b］噁唑［3,4-d］［1,4］噁嗪-3-基】甲基】磷酸单酯二钠盐,其结构经¹H NMR, ¹³C NMR和HR-MS（ESI）确征,总收率7%,纯度99.7%。     

Enantioselective synthesis of piperidine,indolizidine, and quinolizidine alkaloids from a phenylglycinol-derived delta-lactam

Starting from a common lactam, (3R,8aS)-5-oxo-3-phenyl-2,3,6,7,8,8a-hexahydro-5H-oxazolo[3,2-a]pyridine (1), or its enantiomer, the enantioselective synthesis of 2-alkylpiperidines and cis- and trans-2,6-dialkylpiperidines is reported. The potential of this approach is illustrated by the synthesis of the piperidine alkaloids (R)-coniine, (2R,6S)-dihydropinidine, (2R,6R)-lupetidine, and (2R,6R)-solenopsin A, the indolizidine alkaloids (5R,8aR)-indolizidine 167B and (3R,5S,8aS)-monomorine I, and the nonnatural base (4R,9aS)-4-methylquinolizidine.