首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2′氟2′,3′二脱氧腺苷(FddA)及其代谢物2′氟2′,3′二脱氧肌苷(FddI)具有抗HIV的活性。作者用HPLC法同时测定了狗血浆和尿中的FddA和FddI浓度。实验中的内标物质为3′,5′脱水胸苷(IS)。标准品的制备 含有FddA和FddI的血浆和尿标准品的标准曲线范围在血浆中为0.1~20μg·mL-1,在尿中为2~257μg·mL-1。3份血浆对照品(含FddA和FddI为1.0,15.2或50.8μg·mL-1)与2份尿样标准品(含FddA为36.0或366μg·mL-1,含FddI为42.0或420μg·mL-1)经制备后与供试样品一同分析。色谱条件 DuPontZorbaxC8柱(4.6mm×250mm,5μm粒径)…  相似文献   

2.
3.
2-(3′,5′-Di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole (DBHCB) is widely used as a UV absorber. In this study, the developmental toxicity of DBHCB was evaluated in rats. Pregnant rats were given DBHCB at 0, 62.5, 250, or 1000 mg kg?1 day?1 by gavage on days 5–19 of pregnancy. No deaths were observed in the pregnant rats of any group. No effect of DBHCB on the general conditions, body weight gain, or feed consumption was observed in the pregnant rats. There were no changes in the ovarian weight, gravid uterine weight, or necropsy findings in the maternal rats of the DBHCB-treated groups. No significant effects of DBHCB were found in the number of corpora lutea, implantations, live fetuses, resorptions or dead fetuses, incidence of pre- or postimplantation embryonic loss, viability of fetuses, fetal weight, or sex ratio of live fetuses. No significant difference in the incidence of fetuses with malformations or variations or degree of ossification was detected between the DBHCB-treated and control groups.  相似文献   

4.
合成联苯酚醛作为棉酚的最简单的类似物,供药理试验,观察其抗生育作用。  相似文献   

5.
6.
A promising approach to enhancing the bioavailability of hydrophilic therapeutic agents including anti-HIV nucleosides is designing their pseudotriglyceride derivatives that may mimic natural lipids and take advantage of their metabolic pathways resulting in improved delivery to target cells. The synthesis of a series of new 1,3-diglycerides and AZT conjugates employing various linkage types between the pharmacophore residue and the spacer part of the hydrophobic moiety (ester or phosphodiester) is described. The hydrolytic properties of the synthesized liponucleosides (in buffer solutions and under the action of pancreatic lipase) have been studied. Liposomes based on these AZT-containing prodrugs have been obtained.  相似文献   

7.
Purpose. This study examines the central nervous system (CNS) delivery of 2--fluoro-2,3-dideoxyadenosine (F-ddA) and 2--fluoro-2,3-dideoxyinosine (F-ddl), acid stable analogues of dideoxyadenosine (ddA) and dideoxyinosine (ddI) having reduced susceptibility to purine salvage pathway enzymes important in the metabolism of ddA and ddI, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), respectively. Their CNS delivery compared to that for ddI provides insight into the role of brain tissue ADA and PNP in these processes. Methods. Brain and cerebrospinal fluid (CSF) concentration-time profiles were obtained for F-ddI during and after intravenous infusions of F-ddl, and for both F-ddA and F-ddI after F-ddA infusions in normal rats or rats pre-treated with the ADA inhibitor 2-deoxycoformycin (DCF). Rate constants for CNS entry, efflux and metabolism were estimated by computer fits using plasma concentration-time profiles as the driving force functions. Results. The CNS delivery of F-ddI did not differ significantly from that for ddI. F-ddA, which is more lipophilic than F-ddI, provided higher brain ( 8×) and CSF ( 11×) concentrations of total dideoxynucleoside (F-ddA and F-ddI) compared to F-ddI. Deamination by brain tissue ADA to form F-ddI reduced CNS levels of intact F-ddA but provided higher brain parenchyma (5×) and CSF/plasma (3×) ratios of F-ddI relative to F-ddI controls. Thus, F-ddA functions in part as a CNS-activated prodrug of F-ddI. DCF pre-treatment inhibited brain tissue ADA, abolishing the prodrug effect, and enhancing F-ddA concentrations in both brain parenchyma (5×) and CSF (6×). Conclusions. PNP metabolism does not appear to play a role in the low CNS delivery of ddI. On the other hand, deamination of F-ddA by brain tissue ADA is an important process, such that F-ddA functions in part as a CNS-activated prodrug of F-ddI. Enhanced CNS uptake of intact F-ddA can be achieved with ADA inhibition.  相似文献   

8.
目的 改进喜树碱关键中间体5′-RS-,5-二氧代-(5′-乙基-5′-羟基-2′H,5′H,6′H-6-氧代吡喃)-[3′,4′,f]-△^6(8)-四氢中氮茚(1)的合成工艺。方法 以6-氰基-1,1-亚乙二氧基-7-(1′-乙氧羰基)丙基-5-氧代-△^6(8)-四氢中氮茚(2)为原料,经氢化和亚硝化、脱氮、混合金属催化氧化、环合及三氟乙酸脱保护反应得到目标产物。结果与结论 新工艺简化了操作、缩短了反应时间,总产率达到了72.4%。  相似文献   

9.
In the preparation of acyclic thymidine nucleoside analogues, K2CO3 (or NaH) treated thymine in DMSO was alkylated with ω-chloroalkyl nitrite (Cl-(CH2)n-CN; n=1, 2, 3, 4) to provide an isomeric mixture of 1-(ω-cyanoalkyl)thymine (2a-d) and 1,3-bis(ω-cyanoalkyl)thymine in approximately 5∶1 ratios. Reduction of the cyano function2a-d with NaBH4/CoCl2·6H2O gave the corresponding 1-(ω-aminoalkyl)thymine (3a-d). The newly formed primary amino function in3a-d was directly reacted with 2-chloroethylisocyanate to afford the 1-[ω-(N′2-chloroethy-lureido) alkyl]thymine (4a-d) in good yields. Nitrosation of 1-[5-(N′-2-chloroethylureido)pentyl] thymine (4d) with glacial acetic acid and dry NaNO2 powder in anhydrous CH2Cl2 gave two types of regioisomeric nitrosoureas, 1-[5-(N′-2-chloroethyl-N′-nitrosoureido)pentyl]thymine (5d) and 1-[5-(N′-2-chloroethyl-N-nitrosoureido)pentyl]thymine in approximately 5∶1 ratios. The in vitro cytotoxicity of the synthesized compounds (2a-d, 3a-d, 4a-d and5a-d) against three cell lines (K-562, P-388 and FM-3A) are measured as IC50 values. Compounds3d and4c showed moderate activities against all three cell lines, and all other compounds were found to be not active.  相似文献   

10.
11.
以对羟基苯乙酮为原料 ,经硝化和苄醚化合成了平喘药福莫特罗的重要中间体 4′ 苄氧基 3′ 硝基苯乙酮 ,反应总收率为 6 9% ,方法简单、可行 ,适于工业化生产。  相似文献   

12.
2′,4′-二羟基-6′-甲氧基-3′,5′-二甲基查耳酮(DMC)是一种来源于多种植物的查尔酮类天然产物,具有良好的药理活性。本文从理化性质、来源、提取与检测、化学合成、药理活性等方面对DMC的国内外研究进展进行综述,为DMC的前药设计和开发提供参考依据。  相似文献   

13.
14.
Summary The present study in rats was performed to evaluate the cardiotoxic activity of 4 -deoxy-4 -iodo-doxorubicin (4-deoxy-4-I-DXR), a new anthracycline derivative with interesting antineoplastic properties and possible lower cardiotoxicity than doxorubicin (DXR). DXR produced ECG alterations consisting of a progressive and irreversible prolongation of SaT and QaT. In contrast, in 4-deoxy-4-I-DXR-treated rats the increase in SaT and QaT duration was significantly lower than that observed in DXR-treated rats and slightly increased over controls.DXR produced significant histologic changes in myocardium consisting of myocyte vacuolization and myofibrillar loss. No significant modifications were observed in mitochondria. In contrast, no significant cardiac lesions were observed in 4-deoxy-4-I-DXR-treated rats. These results suggest that this new anthracycline derivative has a significantly lower degree of cardiotoxic activity than DXR.  相似文献   

15.
1. An oral dose of the neuroleptic agent 1-(4′-fluor ophenyl)-4-(cyclohexyl-1′-[14 C]piperazinyl-4′-carboxylate)butan-1-one was mainly eliminated in the urine within 12?h by rats and man. During 5 days, 63.6% and 83.3% was eliminated in the urine of rats and man respectively.

2. Plasma concentrations in man reached a maximum during 30 min to 1?h, representing 1.43μg equiv./ml. The proportion of unchanged drug in plasma decreased from 48% at 15 min to less than 10% after 1 h.

3. Seven major radioactive components were detected in the chloroform extract of basified rat urine and five major components in similar extracts of human urine. The major rat metabolites were isolated and identified by mass spectrometry as components resulting from mono- and dihydroxylation in the cyclohexane ring, reduction of the keto group to a secondary alcohol and hydrolysis and decarboxylation of the cyclohexylcarbamoyl group. The major metabolite in the rat urine extract was the dihydroxylated secondary alcohol derivative while the major human metabolite was the monohydroxylated secondary alcohol derivative. The metabolites were also partly eliminated as conjugates.  相似文献   

16.
徐莉  刘捷  徐世平 《药学学报》2001,36(1):29-33
目的 研究3-(3′-甲基-4′-取代苯基-1′,3′-丁二烯基)吲哚类衍生物的合成及其抗癌活性。方法 通过亲电取代、羟醛缩合、选择性还原、相转移Wittig反应和水解反应合成目的化合物,利用几种药理模型进行抗癌和抗炎活性筛选。结果 设计合成了11个3-(3′-甲基-4′-取代苯基-1′,3′-丁二烯基)吲哚化合物,均为新化合物。生物活性实验结果表明,化合物8对HL-60,HCT-8和Bel7402癌细胞株有效,且在浓度为10-5mol·L-1时,其抗炎抑制率可达100%。结论 化合物8显示了抑癌作用和抗炎活性,值得进一步研究。  相似文献   

17.
A series of 1-aryl-4-(3′,4′,5′-trimethoxybenzoyl)piperazines (IIa - IIg) having structures containing 3,4,5-trimethoxybenzoyl fragments were synthesized and characterized. Compounds IIa and IIc - IIg demonstrated weak anxiolytic properties and moderately decreased the spontaneous motor activity in rats. Compound IIb exhibited anxiolytic activity comparable with that of buspirone but, in contrast to this reference drug, increased the motor activity of test animals. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 5, pp. 12 – 14, May, 2005.  相似文献   

18.
Ten, heretofore unreported, 5′-methyl-5′-[2-(5-substituted uracil-1-yl)ethyl)]-2′-oxo-3′-methylenetetrahydrofurans (H, F, Cl, Br, I, CH3, CH3, CH2CH3, CH=CH2, SePh) (7a-j) were synthesized and evaluated against four cell lines (K-562, FM-3A, P-388 and U-937). For the preparation of α-methylene-γ-butyrolactone-linked to 5-substituted uracils (7a-j), the convenient Reformasky type reaction was employed which involves the treatment of ethyl α-(bromomethyl)acrylate and zinc with the respective 1-(5-substituted uracil-1-yl)-3-butanone (6a-j). The 5-substituted uracil ketones (6a-j) were directly obtained by the respective Michael type reaction of vinyl methyl ketone with the K2CO3 (or NaH)-treated 5-substituted uracils (5a-j) in the presence of acetic acid in the DMF solvent. The α-methylene-γ-butyrolactone compounds showing the most significant antitumor activity are7e, 7f, 7h and7j (inhibitory concentration (IC50) ranging from 0.69 to 2.9 μg/ml), while7b, 7g and7i have shown moderate to significant activity. The compounds7a, 7c and7d were found to be inactive. The synthetic intermediate compounds6a-j were also screened and found marginal to moderate activity where compounds6b and6g showed significant activity (IC50:0.4∼2.8 μg/ml).  相似文献   

19.
In our previous toxicity studies using young rats, we showed that an ultraviolet absorber, 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)benzotriazole (HDBB), principally affected the liver, and male rats had nearly 25 times higher susceptibility to the toxic effects than females. In the present study, the toxicity of HDBB was investigated in preweaning rats. HDBB was administered by gavage to male and female CD(SD) rats from postnatal days 4 to 21 at a dose of 0, 0.1, 0.5, 2.5, or 12.5 mg/kg/day. No substance-related deaths, clinical signs of toxicity, or body-weight changes were observed. Increased levels of albumin, AST and ALP in both sexes, BUN in males, and LDH in females were found at 12.5 mg/kg. Liver weights increased at 2.5 mg/kg and above in both sexes. Histopathologically, hepatocellular findings, such as nucleolar enlargement, anisokaryosis, increased mitosis, and/or hypertrophy, were observed at 2.5 mg/kg and above in both sexes. These results indicate no gender-related differences in the susceptibility to the toxic effects of HDBB in preweaning rats.  相似文献   

20.
目的改进喜树碱关键中间体5′-RS-1,5-二氧代-(5′-乙基-5′-羟基-2′H,5′H,6′H-6-氧代吡喃) -[3′,4′,f]-Δ6(8)-四氢中氮茚(1)的合成工艺.方法以6-氰基-1,1-亚乙二氧基-7-(1′-乙氧羰基)丙基-5-氧代-Δ6(8)-四氢中氮茚(2)为原料,经氢化和亚硝化、脱氮、混合金属催化氧化、环合及三氟乙酸脱保护反应得到目标产物.结果与结论新工艺简化了操作、缩短了反应时间,总产率达到了72.4%.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号