1-烷基-5-氨基-6-苯乙基尿嘧啶的合成

研究1-烷基-5-氨基-6-苯乙基尿嘧啶（1a，1b）方便、高产率的合成方法，此类化合物有可能作为非核苷类HIV-1RT抑制剂。以6-甲基尿嘧啶（2）为起始物，经硝化、烷基化、苄基化及一锅反应脱苄基及还原反应等合成目标化合物，并用NMR、MS、IR、Anal鉴定化合物结构。探索出了一种合成1-烷基-5氨基-6-苯乙基尿嘧啶类化合物的方便方法。首次于用3或4步反应、高产率合成了1-烷基-5-氨基-6-苯乙基尿嘧啶（1a，1b）并发现化合物1a有中度抗HIV-1RT的活性（IC50=29μM）。     

1,3-二甲基-6-[2-(对甲苯磺酰氧基)乙基氨基]尿嘧啶的合成

目的:合成盐酸尼非卡兰中间体1,3-二甲基-6-[2-(对甲苯磺酰氧基)乙基氨基]尿嘧啶.方法:以二甲基脲和氰乙酸为原料经3步反应合成目标产物.结果:以氰乙酸计,总收率44.4%.目标产物的光谱数据与文献报道一致.结论:新的合成方法所用原料价廉易得,适合生产.     

琥珀酸曲格列汀的合成及初步HPLC质量控制研究

目的对琥珀酸曲格列汀的合成工艺进行系统研究,为其工艺放大奠定基础。方法以6-氯-3-甲基尿嘧啶为起始原料,通过2次亲核取代、氯化氢-甲醇溶液脱Boc,再与琥珀酸成盐制得琥珀酸曲格列汀。针对采用的特定路线,制备了5种主要有关物质的标准品。结果与结论选用(R)-3-Boc-氨基哌啶引入氨基侧链,可位置选择性地合成曲格列汀,4步反应的总收率达43.1%(以6-氯-3-甲基尿嘧啶计),终产物的纯度达到99.5%以上,单个杂质量均控制在0.1%以下。建立了琥珀酸曲格列汀合成所涉及的各步中间体、目标物及其有关物质的HPLC检测方法,并运用此方法进行合成过程控制及产品质量评价。     

曲匹地尔的合成工艺改进

以氨基碳酸胍和甲酸为原料,一步合成曲匹地尔的中间体3-氨基-1,2,4-三氮唑.该产物可直接进行下步反应,该合成方法所用试剂易得,解决了后处理困难、环境污染等问题,整个反应条件温和,成本较低,收率达61%,适合工业化生产.     

天然产物曼宋酮E和F的合成工艺改进

目的改进天然产物曼宋酮E和F的合成工艺。方法以2,5-二甲基萘醌为原料,经过8步反应得到曼宋酮F,经过9步反应得到曼宋酮E。其中,在二酯的选择性水解反应步骤、关环策略以及最后氧化为邻醌的氧化剂选择方面做了有效的改进。结果与结论产物经结构确证为曼宋酮E和F。曼宋酮F最后连续5步反应收率可达49%。改进后的合成路线提高了收率,降低了成本,多步反应可连续进行,减少了中间产物分离纯化环节。     

6-氨基尿嘧啶合成的改进

6-氨基尿嘧啶广泛用于合成含嘧啶环化合物的中间体,其中包括磺胺类药物。氰乙酰基脲于浓碱液中环化,继而在酸作用下析出,是制取6-氨基尿嘧啶的最经济简便方法。通常在环合反应进行的同时发生氰乙酰基脲水解的副反应。当降低碱的浓度和提高温度时,可使水解作用加快。同时在     

苯甲酸阿格列汀合成工艺的改进

目的改进苯甲酸阿格列汀的合成工艺。方法以6-氯尿嘧啶为起始原料,先与碘甲烷反应合成3-甲基-6-氯尿嘧啶,继而在无机碱的参与下与2-溴甲基苄腈反应得2-(6-氯-3甲基-2,4-二氯代-3,4-二氢-2H-嘧啶-1-基甲基)-苄腈,然后再在无机碱的存在下与(R)-3-氨基哌啶二盐酸发生取代反应,最后与苯甲酸成盐得苯甲酸阿格列汀。结果合成得到苯甲酸阿格列汀,总收率达到57.09%,纯度为99.6%。结论该工艺经过改进,降低了毒害,成本降低,经济环保,适合工业化生产。     

阿法骨化醇合成的新方法

目的：合成阿法骨化醇。方法：以维生素D3为原料，经酯化、关环、氧化、开环、水解5步反应合成目标化合物。结果：本方法避开了光照反应，产物总收率为17．2％。结论：本方法提高了收率，操作安全，适合于工业化生产。     

磷酸二酯酶9A抑制剂LW33的合成

目的:改进LW33的制备工艺。方法:以2,4,6-三氯-5-嘧啶甲醛和环戊基肼盐酸盐为起始原料,通过3步反应合成了磷酸二酯酶9A(PDE 9A)抑制剂LW33{(S)-6-[1-(4-氯苯基)乙氨基]-1-环戊基-吡唑并[3,4-d]嘧啶-4-酮}。结果:目标产物结构经1H核磁共振(1H-NMR)、13C核磁共振(13C-NMR)和电喷雾质谱(ESI-HRMS)确证,纯度经高效液相色谱(high performance liquid chromatography,HPLC)法检测可达99.9%,路线总收率达43.6%。结论:改进后的制备工艺反应条件温和、操作简单、产物纯度好、收率高,适合用于工业化生产。     

6-氨基-1-丙基-尿嘧啶的合成

6-氨基-1-丙基-尿嘧啶是合成嘌呤及嘌呤衍生物的医药中间体,目前为止国内没有生产的,经多次试验确定以丙基脲,氰乙酸,酸酐为原料,通过亲核反应,再在氢氧化钠的作用下合环生成6-氨基-1-丙基-尿嘧啶,此合成总收率〉70%。     

Comparative metabolic disposition of [1-Me14C]caffeine in rats, mice, and Chinese hamsters

The metabolic disposition of [1-Me14C]caffeine has been studied and compared in three male rodent species: the rat, the mouse, and the Chinese hamster. No interspecies differences appeared in urinary and fecal excretion of radioactivity. However, 1-methyldemethylation was significantly more important in the rat with 20.6 +/- 0.8% of the dose recovered as 14CO2 compared with the Chinese hamster, 16.1 +/- 2%, and the mouse, 13.9 +/- 0.9%. HPLC and TLC analysis of 1-methyl-labeled metabolites showed that the rat exhibits a significantly higher urinary excretion of the four trimethyl derivatives: caffeine, 1,3,7-trimethyluric acid, trimethylallantoin, and 6-amino-5-[N-formylmethylamino]-1,3-dimethyluracil [40.8% of total urine radioactivity) when compared with the Chinese hamster (21.1%) and the mouse (19.7%). Compared with man (6%), these rodents have a greater ability to excrete caffeine without any demethylation. The rat was also characterized by a higher excretion of theophylline while the Chinese hamster excreted more paraxanthine, 1-methylxanthine, and the uracil derivative of paraxanthine. In the mouse, in addition to 1-methylxanthine and 1-methyluric acid, higher amounts of 1,3- and 1,7-dimethyluric acid were found. The mouse was particularly characterized by the presence of an unknown polar metabolite amounting to 22 +/- 3% of urine radioactivity. This metabolite must be produced from paraxanthine because its quantitative formation was inversely related to the excretion of paraxanthine and its metabolites. The observations that this metabolite is neither 5-acetylamino-6-amino-3-methyluracil nor 5-acetylamino-6-formylamino-3-methyluracil reported in humans demonstrate that both quantitative and qualitative interspecies differences occur for caffeine metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)     

In vitro and in vivo cytotoxicity of possible uracil metabolites of methylxanthines

The present study was designed to elucidate the cytotoxic potential of 8 possible substituted uracilic metabolites of methylxanthines. 5-Fluorouracil (5-FU) was used as a reference uracil analogue with cytotoxic activity. Substituted uracil derivatives examined in this study did not affect the proliferative capacity of PHA-stimulated rat lymphocytes, murine L1210 leukaemia and rat chondrocytes. Caffeine had some growth inhibitory activity of extremely high concentrations (greater than 100 micrograms/ml). In vivo administration of 6-amino-5[N-methyl-formylamino]1,3-dimethyluracil (1,3,7-TAU) and 6-amino-5[N-acetylamino]3-methyluracil (7-A3-MAU) caused a transient short-lived reduction of L1210 tumour cell numbers. These observations do not appear to support the hypothesis that substituted uracils are involved in the toxicity of high doses of caffeine in rats.     

来那度胺的合成

N-(叔丁氧羰基)-L-谷氨酰胺(2)经分子内环合、脱保护得中间体3-氨基-2,6-哌啶二酮三氟乙酸盐(4);另用2-甲基-3-硝基苯甲酸甲酯(5)经溴化制得另一中间体2-溴甲基-3-硝基苯甲酸甲酯(6).4与6经缩合、还原制得来那度胺,总收率约33%(以5计).     

Theobromine metabolism in man

The effects of allopurinol on the plasma clearance and metabolism of theobromine have been investigated under multiple-dosing conditions. Allopurinol had no effect on the clearance of theobromine, indicating that the elimination of this compound is dependent on enzyme systems other than xanthine oxidase, presumably the hepatic mixed-function oxidases. The excretion of 3-methylxanthine, 6-amino-5-(N-methylformylamino)-1-methyluracil, and unchanged theobromine were similarly unaffected by the allopurinol treatment. Although allopurinol abolished the formation of 7-methyluric acid (7MU) and increased the excretion of 7-methylxanthine (7MX), the metabolic clearance to (7MX + 7MU) was not significantly different with and without allopurinol. It is proposed that the secondary biotransformation of 7MX to 7MU is mediated by xanthine oxidase.     

Synthesis and biological activities of 5-deaza analogues of aminopterin and folic acid

N-[p-[[(2,4-Diaminopyrido[2,3-d]pyrimidin-6-yl)methyl] amino]benzoyl]-L-glutamic acid (1a, 5-deazaaminopterin) and the 5-methyl analogue (1b) were synthesized in 14 steps from 5-cyanouracil (4a) and 5-cyano-6-methyluracil (4b), respectively, by exploitation of the novel pyrimidine to pyrido[2,3-d]pyrimidine ring transformation reaction. The 5-cyanouracils 4 were treated with chloromethyl methyl ether to the 1,3-bis(methoxymethyl)uracils (5, which were treated with malononitrile in NaOEt/EtOH to give the pyrido[2,3-d]pyrimidines 6. Diazotization of 6 in concentrated HCl afforded the 7-chloro derivatives 8 in high yield. After reduction of 8, the 7-unsubstituted products 9 were reduced in the presence of Ac2O and the products, 6-(acetamidomethyl)pyridopyrimidines 10, were converted into the 6-acetoxymethyl derivatives 12 via nitrosation. After removal of the N-methoxymethyl groups from 12, the 6-(acetoxymethyl)pyrido[2,3-d]pyrimidine-2,4(1H,3H)-diones 14 were converted into 2,4-diamino-6-(hydroxymethyl)pyrido[2,3-d]pyrimidine (15a) and its 5-methyl analogue 15b by the silylation-amination procedure. Compounds 15 were brominated to the 6-bromomethyl derivatives 16, which were treated with diethyl (p-aminobenzoyl)-L-glutamate, and the products 17 were saponified to afford 5-deazaaminopterin (1a) and its 5-methyl analogue 1b. Compound 1b was also prepared by an alternative procedure in 10 steps from cyanothioacetamide and ethyl beta-(ethoxymethylene)acetoacetate via 2,4-diamino-6-(hydroxymethyl)-5-methylpyrido[2,3-d]pyrimidine (15b). 5-Deaza-5-methylfolic acid (2) was also prepared in four steps from 15b. The aminopterine analogues 1 showed significant anticancer activity in vitro and in vivo, whereas the folic acid analogue 2 did not exhibit any significant toxicity.     

Stability of 5-acetamido-6-formylamino-3-methyluracil in buffers and urine

The caffeine metabolite 5-acetamido-6-formylamino-3-methyluracil (AFMU) and its product of spontaneous deformylation 5-acetamido-6-amino-3-methyluracil (AAMU) were synthesized. Their ultraviolet absorption spectra differed significantly from each other and wavelengths of absorption maximum and molar extinction coefficients varied with pH. The changes of the absorption spectrum parameters of AFMU and AAMU with pH indicated that they ionized with pK(a) of 5.7 and 8.3, respectively. The spontaneous deformylation of AFMU in solutions of different pH and urine were investigated spectrophotometrically and by high-performance liquid chromatography. The data showed the following: (a) AFMU transformed uniquely to AAMU; (b) deformylation obeyed first-order kinetics under the different conditions tested; (c) the half-life of AFMU varied between 7.8 and 36 h between pH 9.0 and 2.0 at 24 degrees C, with a maximum of 150 h at pH 3.0; (d) AFMU deformylated below pH 2.0 and above pH 10.0 with a half-life of less than 4.6 h; (e) half-lives of AFMU in urine were 57 and 12.5 h at 24 and 37 degrees C, respectively, comparable to those in buffers at equivalent pH and temperature. The results are discussed in relation to the mechanism of deformylation and the use of caffeine as a probe drug for NAT2 phenotyping.     

Synthesis and potential biological activity of some novel 3-[(N-substituted indol-3-yl)methyleneamino]-6-amino-4-aryl-pyrano(2,3-c)pyrazole-5-carbonitriles and 3,6-diamino-4-(N-substituted indol-3-yl)pyrano(2,3-c)pyrazole-5-carbonitriles

Starting from N-substituted indole-3-carboxaldehydes (1a-g) a series of new 3-[(N-substituted indol-3-yl)methyleneamino]-6-amino-4-aryl-pyrano(2,3-c)pyrazole-5-carbonitriles (3a-g and 4a-g) have been synthesized via the acid catalyzed condensation reaction of 1a-g with 3-amino-5-pyrazolone, followed by the reaction with arylidene malononitriles. A series of new 3,6-diamino-4-(N-substituted indol-3-yl)pyrano(2,3-c)pyrazole-5-carbonitriles (7a-g) have been prepared either via the base catalyzed condensation reaction of 1a-g with 3-amino-5-pyrazolone to give 6a-g, followed by the reaction with malononitrile or by the reaction of N-substituted-3-indolylidene malononitriles (5a-g) with 3-amino-5-pyrazolone. According to the obtained results, the newly synthesized compounds possess significant anti-inflammatory, analgesic and anticonvulsant activities. The anticonvulsant potency of certain tested compounds was more pronounced than both anti-inflammatory and analgesic activities. Moreover, most of the newly synthesized compounds possess potential antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa.     

(2S, 3S)-3-氨基-2-羟基-4-苯丁酰胺的合成

目的 合成α-酮基酰胺肽类钙蛋白酶抑制剂的必需结构片段 (2S, 3S)-3-氨基-2-羟基-4-苯丁酰胺（1）。 方法 以(S)-2-氨基-3-苯丙醇为起始原料,经过苄基保护、Parikh-Doering 氧化、氰化水解、酰胺化和脱保护共5步反应合成目标化合物。结果与讨论 目标化合物和中间体的结构均经1H-NMR和13C-NMR谱确证,该合成路线方法简捷,适于大量制备。     

Potential inhibitors of L-asparagine biosynthesis. 5. Electrophilic amide analogues of (S)-2,3-diaminopropionic acid

Three electrophilic amide analogues of (S)-2,3-diaminopropionic acid (1, DAP) have been prepared as potential inhibitors of L-asparagine synthetase (ASase, from Novikoff hepatoma, EC 6.3.5.4). DAP was selectively blocked by the carbobenzoxy (Cbz) group to give 3-N-Cbz-DAP (2a). Esterification of 2a with isobutylene afforded tert-butyl 3-N-carbobenzoxy-(S)-2,3-diaminopropionate (3a), which was then blocked at the 2 position with the tert-butoxycarbonyl (Boc) group to give tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-[(carbobenzoxy)amino]propionate (4). Selective cleavage of the Cbz group by H2/Pd gave the key intermediate tert-butyl 2-N-(tert-butoxycarbonyl)-(S)-2,3-diaminopropionate (5), which was acylated, via the N-hydroxysuccinimide esters, with bromoacetic acid, dichloroacetic acid, and fumaric acid monoethyl ester to give tert-butyl 2-[(S)-(tert-butoxycarbonyl)-amino]-3-(2-bromoacetamido)propionate (6a), tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-(2,2-dichloroacetamido)propionate (6b), and tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-(ethoxycarbonyl)acrylamido]-propionate (6c), respectively. Deblocking of 6a-c gave the corresponding amino acids (S)-2-amino-3-(2-bromoacetamido)propionic acid hydrobromide (7a), (S)-2-amino-3-(2,2-dichloroacetamido)propionic acid (7b), and ethyl N-[(S)-2-amino-2-carboxyethyl]fumarate (7c). By a slightly different procedure, 5 was converted in two steps to (S)-2-amino-3-acetamidopropionic acid hydrobromide (7d). The inhibition of ASase by 7a-c at 1 mM was 93, 19, and 37%, respectively, while 7d was without inhibition at 2 mM. Compounds 7a-c failed to increase the life span of mice infected with B16 melanoma.