Chronic toxicity and carcinogenicity of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame) in the rat

Groups of 55 male and 55 female Han Wistar rats were administered advantame (98.9-99.8% purity) in the diet at concentrations of 0, 2000, 10,000, or 50,000 ppm for 104 weeks, following parental exposure to the same levels from prior to mating and throughout gestation. Additional groups of 20 rats/sex and 10 rats/sex were dosed for a period of 52 weeks and constituted the toxicity and reversibility phases of the study. Achieved doses of advantame over the carcinogenicity study were 0, 97, 488, and 2621 mg/kg body weight/day in males and 0, 125, 630, and 3454 mg/kg body weight/day in females, respectively. A high incidence of a pale and swollen anus and changes in fecal composition were observed in the high-dose groups. There was no effect of treatment on mortality. Body weight gain in the high-dose males (50,000 ppm) was slightly reduced compared to controls after 52 and 104 weeks of treatment; the decrease was not considered to be of toxicological significance, but due to the non-nutritive nature of the high dietary concentration of advantame. During the toxicity phase, food conversion efficiency was slightly decreased in both sexes, at the 50,000 ppm dose level. Given the non-nutritive content of the diet, this finding was not considered biologically significant. There were no relationships between treatment and the results of hematological or urinalysis investigations. Clinical chemistry evaluations showed consistently lower plasma urea concentrations in both sexes treated at 50,000 ppm, which was reversed during the 6-week recovery phase following 52 weeks of treatment, indicating a lack of permanent effects. Terminal investigations at both the 52 and 104-week revealed a number of intergroup differences in absolute and/or relative organ weights; however, the differences did not show dose-response relationships, were minor in nature, and/or occurred only in one sex, and were not associated with any pathological findings, and they were considered not to be treatment-related. Evaluation of the histopathology of the carcinogenicity phase animals revealed an increased incidence of pancreatic islet cell carcinomas in males (incidence rates of 0/55, 1/55, 2/55, and 3/55 in the 0, 2000, 10,000, or 50,000 ppm groups, respectively) and of mammary gland adenomas in the high-dose females (incidence rates of 0 in the control through 10,000 ppm dose groups and 4/41 in the 50,000 ppm dose group). The incidence rates of these tumors did not attain statistical significance and/or remained within background historical control values, and they were considered to be unrelated to advantame treatment. The no-observed-adverse-effect level was considered to be 50,000 ppm in the diet, the highest concentration tested, equivalent to 2621 and 3454 mg/kg body weight/day in males and females, respectively. Advantame was concluded to be without carcinogenic activity.     

In vitro and in vivo assessment of the mutagenic activity of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame)

Advantame (N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate), an N-substituted analogue of aspartame, has been developed as a high-intensity sweetener. It is approximately 100 and 20,000 times sweeter than aspartame and sucrose, respectively. In this study the safety of advantame has been evaluated using a series of in vitro and in vivo genotoxicity assays including, bacterial mutation, mammalian cell mutation, and mouse micronucleus tests. Advantame did not induce reverse mutations in Salmonella typhimurium and Escherichia coli at concentrations of up to 5000 μg/plate. In the mammalian cell mutation assay, advantame did not induce mutation at the Hprt locus of L5178Y mouse lymphoma cells in two independent experiments, either in the absence or presence of S9. In vivo, there was no effect on the incidence of micronucleated immature or mature erythrocytes in bone marrow after oral administration of the test substance at any dose level (up to 2000 mg/kg body weight) or sampling time (24 and 48 h). The results of these studies demonstrate that advantame is without genotoxic potential.     

Chronic oral toxicity of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame) in the dog

Advantame (N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate), an N-substituted analog of aspartame, has been developed as a high-intensity sweetener. Groups of 4 dogs of each sex were treated at 0, 2000, 10,000, or 50,000 ppm of advantame in the diet for 52 weeks. Additional groups of 2 dogs/sex at the control, and mid- and high-dose groups were treated for 52 weeks followed by a 6-week recovery period. There was no effect of treatment on mortality, body weight, organ weights, food consumption, or the results of ophthalmological, electrocardiographic, haematological, clinical chemistry or urinalysis examinations. No histopathological changes were associated with advantame treatment. The NOAEL was considered to be 50,000 ppm, the highest concentration tested, which was equivalent to 2057 and 2139 mg/kg body weight/day in males, and females, respectively. The results of the study support the safety of advantame for use as a high-intensity sweetener.     

Evaluation of the teratogenic potential of N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate (advantame) in the rat and rabbit

To assess its teratogenic potential, advantame (N-[N-[3-(3-hydroxy-4-methoxyphenyl) propyl]-α-aspartyl]-L-phenylalanine 1-methyl ester, monohydrate) was administered to mated rats (22/group) in the diet at 0, 5000, 15,000, and 50,000 ppm (providing approximately 465, 1418, and 4828 mg/kg body weight/day), and to mated rabbits (24/group) via oral gavage at 0, 500, 1000, and 2000 mg/kg body weight/day throughout gestation. Shortly before delivery (rats: day 20; rabbits: day 29), animals were killed and subjected to a detailed necropsy. Fetuses were examined for external, visceral, and skeletal alterations. Atypical coloration of the feces and cage liners seen with test diets in both rats and rabbits was attributed to excretion of test material/metabolites in the feces and urine. Advantame had no adverse effect on rat offspring survival or development. The no-observed-adverse-effect level (NOAEL) for both maternal and developmental toxicity in rats was 50,000 ppm, the highest dietary concentration tested. Due to adverse effects associated with reduced food intake and fecal output, approximately 20% of mated rabbits receiving 200 0mg/kg body weight/day and 1 animal at 1000 mg/kg body weight/day had to be terminated before scheduled necropsy. A NOAEL of 500 mg/kg body weight/day was established for maternal toxicity in rabbits. No teratogenic effects were observed in any animals, and based on a slightly increased incidence of fetal deaths at 2000 mg/kg body weight/day, a finding that was considered to be indirectly related to advantame treatment, 1000 mg/kg body weight/day was considered the NOAEL for developmental toxicity.     

4-[2-(N-甲基,N-(2-吡啶基)氨基)-乙氧基]苯甲醛的合成方法改进

目的:改进罗格列酮的关键中间体4-[2-(N-甲基,N-(2-吡啶基)氨基)-乙氧基]苯甲醛的合成方法。方法:以2-[N-甲基,N-(2-吡啶基)氨基]乙醇为原料,分别与对氟苯甲醛发生威廉森成醚反应(以乙腈作溶剂,KOH作去酸剂)及与对羟基苯甲醛发生脱水缩合反应,合成目标化合物。结果:得到目标化合物,其结构经1HNMR和MS验证。结论:两种改进的合成方法操作简便,适于工业化生产。     

Synthesis of 2-(Alkylthio)-1,2,4-triazolo[1,5-a]pyrimidines and 3-(Alkythio)-1,2,4-triazolo[3,4-a]pyrimidines and Their Vasodilator Activity

本文作者合成了新的５，７二甲基１，２，４三唑并［１，５ａ］嘧啶２苄硫醚类（Ｂ系列）５，７二甲基１，２，４三唑并［３，４ａ］嘧啶２苄硫醚类化合物（Ｄ系列），并测定了这两类化合物在体外对８５７ｍｍｏｌ·Ｌ１Ｋ＋和１０４ｍｍｏｌ·Ｌ１ＮＥ（ｎｏｒｅｐｉｎｅｐｈｒｉｎｅ）引起的血管条收缩的抑制作用。测定结果表明，Ｂ系列化合物的活性均高于Ｄ系列化合物，在苯环的对位有体积较大的疏水性基团有助于生物活性的提高。５，７二甲基１，２，４三唑并［１，５ａ］嘧啶２对溴苄硫醚表现出最好的扩张血管活性，在浓度为１０５ｍｏｌ·Ｌ１和１０４ｍｏｌ·Ｌ１时，对１０４ｍｍｏｌ·Ｌ１ＮＥ引起的离体血管条痉挛的抑制率均为１００％；对８５７ｍｍｏｌ·Ｌ１Ｋ＋引起的离体血管条痉挛的抑制率分别为４７％和１００％。     

N-[3',3'-双(膦羧基)丙基]-3-{4-[双(2-氯乙基)氨基]苯基}-3-氨基丙酰胺的合成及表征

目的合成N-[3’,3’-双(膦羧基)丙基]-3-{4-[双(2-氯乙基)氨基]苯基}-3-氨基丙酰胺,并进行体外骨靶向性实验。方法以3,3-双(二乙氧膦酰基)-1-硝基丙烷(1)为原料,经氢化还原,再与N-苄氧羰酰异苯丙氨酸氮芥(2)偶联,催化氢化还原得到化合物(4),用溴代三甲基硅烷脱去膦酸酯的烷基得到目标化合物T。用羟磷灰石晶体作为骨模型,测定偶联物T的趋骨性。结果和结论目标物T经1HNMRI、R、MS得到结构确证,体外骨靶向性实验显示,目标物T有良好的骨靶向性。     

N-[2-(4-甲氧基苯基)-1-甲基乙基]苄胺的制备

以1-（4-甲氧基苯基）丙酮-2和N-苄基甲酰胺为原料,采用“一锅法”,经N-苄基化、Leuckart反应和酸性水解制得福莫特罗的重要中间体N-[2-（4-甲氧基苯基）-1-甲基乙基]苄胺,总收率约46%。     

Microwave-accelerated preparation and analytical characterization of 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]- and [α,α,β,β-D(4) ]-tryptamines

The increased interest in N,N-dialkyl tryptamines is a reflection of their diverse range of biologically active properties. Deuterated derivatives are of interest for use as internal standards in bioanalytical or pharmacological assays. The present study reports on the synthesis of twelve novel 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]-tryptamines and their [α,α,β,β-D(4) ]-counterparts following the Speeter and Anthony procedure. The normally time-consuming reduction step was carried out in 5 min under microwave-accelerated conditions. Good yields were obtained using tetrahydrofuran as the solvent at 150 °C. The resulting 24 tryptamines have been characterized by 1D/2D nuclear magnetic resonance spectroscopy and gas chromatography ion trap mass spectrometry. Differential fragmentation of side-chain-related iminium ions has been observed as a key principle. Because many N,N-dialkyltryptamines are available outside of traditional pharmaceutical supply chains as so-called 'research chemicals', the availability, as standards, of these new N,N-dialkyltryptamines will aid in identifiying novel tryptamines arising from these other souces. They should therefore be of immediate value within forensic, research, and public health contexts.     

Uterotrophic assay,Hershberger assay,and subacute oral toxicity study of 4,4´-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bis[phenol] based on the OECD draft protocols

We performed an uterotrophic assay, the Hershberger assay, and a 28-day repeated-dose toxicity study (enhanced OECD test guideline No. 407) of 4,4′-[1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene]bis[phenol] based on the OECD draft protocols. In the uterotrophic assay, female SD rats were subcutaneously injected with the chemical at doses of 0, 100, 300, and 1,000 mg/kg on each of 3 days from postnatal day 20 to day 22, and the uterine weight of rats given the 1,000 mg/kg dose of the test chemical plus ethinyl estradiol decreased. In the Hershberger assay, the test chemical was orally administered at doses of 0, 100, 300, and 1,000 mg/kg day to castrated male SD rats for ten consecutive days beginning on postnatal day 56, and no changes were observed. On the other hand, when the test chemical was orally administered at doses 0, 100, 300, and 1,000 mg/kg day for at least 28 days, a decrease in LH values in rats of both sexes and a decrease in FSH and estradiol values in female rats were detected in the 1,000 mg/kg group, and abnormal estrous cycles, uterine glandular atrophy, persistence of ovarian corpora lutea, vaginal epithelial mucification, and mammary glandular hyperplasia were also observed in one female rat in the 1,000 mg/kg group. Therefore, the uterotrophic assay used in this study showed that the chemical has the estrogen–antagonist properties, and some potentially endocrine-mediated effects were detected in growing rats based on the results of the enhanced OECD test guideline No. 407. However, the changes were observed in rats given a high dose of the chemical, 1,000 mg/kg day.     

Binding characteristics of (+)-, (±)- and (-)-[125Iodo] cyanopindolol to guinea-pig left ventricle membranes

Summary [¹²⁵Iodo]cyanopindolol [(±)-ICYP], a potent and selective ligand for -adrenoceptors, exhibited complex biphasic dissociation kinetics. Consequently, in receptor binding studies, the pure (+)- and (-)-enantiomers of ICYP were synthesised and their equilibrium and kinetic binding characteristics were investigated on a membrane preparation of guinea pig left ventricle containing almost only ₁-adrenoceptors.All three ligands, i. e. (+)-, (-)- and (±)-ICYP, bind to -adrenoceptors as assessed by competition experiments with different -blocking agents; irrespective of the ligand used, the same dissociation constant was found for the competitor. In a first series of saturation binding experiments performed in a low concentration range of free ligand (0–250 pM), ICYP showed the following dissociation constants: K _D=93, 9 and 23 pM, and number of binding sites: B _max=40,128 and 124 fmoles/mg protein for (+)-, (-)-, and (±)-ICYP, respectively. Asexpected, (±)-ICYP showed the same B _max as (-)-ICYP, whereas its K _D was approximately two times higher than that of (-)-ICYP. Surprisingly, the B _max of (+)-ICYP represented only 30% of the B _max of (-)-ICYP. All three ligands bound apparently to a single class of binding sites.In dissociation experiments, the enantiomers of ICYP showed biphasic dissociation curves as observed for the racemic ligand. (+)-, (-)- and (±)-ICYP showed a rapidly dissociating (k _-1=0.488, 0.047 and 0.049 min^–1) and a slowly dissociating component (k _-2=0.0205, 0.0033 and 0.0025 min^–1). The ratio slow dissociating/fast dissociating component represented respectively for (+)-, (-)- and (±)-ICYP 40/60, 90/10 and 90/10. For all three ligands, the association rate constants were of the same order of magnitude (ca. 10⁹ M^–1 min^–1), typical for a diffusion controlled reaction.In contrast to equilibrium binding studies, the existence of multiple receptor affinity sites was evident from the biphasic dissociation behaviour observed especially with the nonracemic ligands (+)-ICYP and (-)-ICYP.Simulation of theoretical saturation curves performed with the ratios of high versus low affinity sites and the K _D-values suggested by kinetic analysis, indicated that the delineation into two affinity states might be visible in saturation experiments, under certain conditions.Therefore, equilibrium binding studies were repeated with an increased number of ligand concentrations covering a large concentration range of 0–800 pM. Simultaneous analysis of saturation curves from the same experiment using three different ligands, provided more accurate estimates of the ratio of high and low affinity sites, as well as the affinity constants of the ligand for each receptor affinity state, in good agreement with the results from kinetic analysis.The contribution of the (+)enantiomer in the binding of the racemic ligand under low receptor concentrations could be neglected since dissociation characteristics of (±)- and (-)-ICYP were identical. A model that explains the biphasic dissociation of (±)-ICYP by differential binding of both enantiomers could be rejected. Kinetic and equilibrium binding characteristics of the three radioligands were not influenced by the guanylnucleotide Gpp(NH)p (10^–4 M).The antagonist ICYP binds to -adrenoceptors in a high and low affinity state which are probably interconvertible.Abbreviations CYP cyanopinodolol - ICYP [¹²⁵Iodo]cyanopindolol - HYP (±)-hydroxybenzylpindolol - IHYP (±)-[¹²⁵Iodo]hydroxybenzylpindolol - ³H-DHA (-)-[³H]dihydroalprenolol - ³H-HBI (±)-[³H]-hydroxybenzylisoproterenol - ISA intrinsic sympathomimetic activity; Gpp(NH)p, guanyl-5yl-imidodiphosphate - FM 24 1-(2-exobicyclo[2,2,1]hept-2yl-phenoxy)-3-[(1-methylethyl)amino]-2-propranolol Part of this work has been presented at the Spring Meeting of the German Pharmacological Society, Mainz, March 10–13, 1981     

呋喃丙胺[N-异丙基-β-(5-硝基-2-呋喃)丙烯酰胺]-C~(14)的合成

呋喃丙胺(又称F-30066)(Ⅵ)是我国发现的非锑类型抗日本吸血虫病口服药物。经动物试验和临床研究证明,它对日本血吸虫病有显著疗效。为了进一步探讨它在体内作用机制及分布、代谢情况,我们曾合成其C~(14)标记化合物。合成途径是以C~(14)-碳酸钡为原料制成1-C~(14)乙酸钠,酸化成1-C~(14)-乙酸,经溴化、酯化成1-C~(14)-溴乙酸乙酯(Ⅰ),1-C~(14)-溴乙酸乙     

(2R,3S)-2-[(R)-1-[3,5-二(三氟甲基)苯基]乙氧基]-3-(4-氟苯基)吗啉盐酸盐的合成

对甲氧基苯甲醛(3)和2-氨基乙醇进行还原胺化反应得2-(4-甲氧基苄胺基)乙醇(4),4和乙醛酸经成环反应得2-羟基-4-对甲氧基苄基吗啉-3-酮(5),5和三氟乙酐反应得6后与(R)-1-[3,5-二(三氟甲基)苯基]乙醇(7)缩合,再经结晶诱导不对称转化、格氏反应、氢化脱保护及成盐反应制得阿瑞吡坦关键中间体(2R,3S)-2-[(R)-1-[3,5-二(三氟甲基)苯基]乙氧基]-3-(4-氟苯基)吗啉盐酸盐,总收率约18%(以3计)。     

Synthesis and in vitro antitumor activity of new quinoline, pyrimido[4,5-b]quinoline, [1,2,3]triazino[4,5-b]quinoline, and [1,2,4]triazolo[2′,3′:3,4]pyrimido[6,5-b]quinoline analogs

New series of quinoline, pyrimido[4,5-b]quinoline, [1,2,3]triazino[4,5-b]quinoline, and [1,2,4]triazolo[2′,3′:3,4]pyrimido[6,5-b]quinoline analogs have been synthesized and characterized by analytical and spectrometrical methods (IR, ¹H NMR, ¹³C NMR, MS). Fifteen of the newly synthesized compounds; namely, 3a, b, 4b, 6a, b, 10a–f, and 14a–d were evaluated for their in vitro antitumor activity at the National Cancer Institute (NCI) 60 cell lines panel assay. Compounds 4b and 10f are the most active members in this study, demonstrating significant broad spectrum antitumor activity against most of the tested sub-panel tumor cell lines. The detailed synthesis, spectroscopic, and biological data are described.     

Synthesis of novel 2-(3′-aryl-sydnon-4′-ylidene)-5′-substituted-[1,3,4]-thiadiazolylamines and [1,3,4]-thiadiazol-2′-yl-3-oxo-[1,2,4]-triazoles as antimicrobial agents

The title compounds (3g–n) and (6g–n) were synthesized using 3-arylsydnones as synthons, and the structures were confirmed by IR, ¹H NMR, FAB mass and CHN analysis. These compounds were evaluated for their antibacterial and the antifungal activities in terms of minimum inhibitory concentrations (MICs) against the bacterial strains E. coli, B. cereus, and the fungal strains A. niger, C. albicans. Some of the compounds have shown significant activities.     

Synthesis and Antiarrhythmic Activity of N-[2-(Adamantan-2-YL)Aminocarbonyl-Methyl-N′-(Dialkylamino)Alkylnitrobenzamides

Pharmaceutical Chemistry Journal - Novel 2-aminoadamantane derivatives, specifically N-[2-(adamant-2-yl)-aminocarbonylmethyl]-N′-(dialkylamino) alkylnitrobenzamides and their physiologically...     

A novel tertiary pyridostigmine derivative [3-(N,N-dimethylcarbamyloxy)-1-methyl-Δ3-tetrahydropyridine]: Anticholinesterase properties and efficacy against soman

In an effort to develop an effective centrally acting pretreatment compound against organophosphorus poisons, the tertiary pyridostigmine (Pyr) derivative 3-(N,N-dimethylcarbamyloxy)-1-methyl-Δ³-tetrahydropyridine (THP) was synthesized and studied for its anticholinesterase properties, as well as its efficacy against soman intoxication in guinea pigs. Injection of THP (262 μg/kg, im) into adult male guinea pigs caused inhibition of blood (30%) and brain (25%) acetylcholinesterase (AChE), showing that THP penetrates the blood-brain barrier. Pyr (131 μg/kg, im) caused AChE inhibition in the blood (59%), but not in the brain. The inhibitory potencies of THP and Pyr were compared by determining their IC50 values for in vitro inhibition of both AChE (brain, erythrocyte) and pseudo-cholinesterase (plasma) in three mammalian species (guinea pig, rat, rabbit). THP, although effective in inhibiting both types of cholinesterase, was in general less potent than Pyr. Pretreatment of guinea pigs with THP 9262 μg/kg, im) plus Pyr (131 μg/kg, im), 30 min prior to subcutaneous soman challenge, with no antimuscarinic or oxime treatment, protected 60% of the animals against 2 × LD50 of soman. Neither THP nor Pyr alone was effective. The protective pretreatment regimen did not prevent convulsions, but shortened the recovery time in surviving animals (median recovery time 1.6 hr, compared to 24 hr in control and other groups of animals pretreated with THP or Pyr alone). A combination of THP and Pyr thus appears to provide a means of evaluating the relative importance of selective peripheral plus central vs peripheral AChE protection against soman.     

Synthesis and anti-HIV-1 screening of novel N′-(1-(aryl)ethylidene)-2-(5,5-dioxido-3-phenylbenzo[e]pyrazolo[4,3-c][1,2]thiazin-4(1H)-yl)acetohydrazides

A novel series of N′-(1-(aryl)ethylidene)-2-(5,5-dioxido-3-phenylbenzo[e]pyrazolo[4,3-c][1,2]thiazin-4(1H)-yl)acetohydrazides was synthesized. The synthesis was carried out by thermal method as well as ultrasonic bath to reduce reaction time and to enhance product yields. The synthesized compounds were characterized by spectroscopic techniques like NMR, infrared and EIMS. The structure of compound 5w was elucidated by X-ray crystallography. The titled compounds were evaluated for anti-human immunodeficiency virus type 1 (anti-HIV-1) and cytotoxic activities. Biological studies indicated that amongst these compounds, 5a, b, j, h and i showed the activity with median effective concentration (EC₅₀) values less than 20 μM. Compound 5i exhibited the most potent anti-HIV-1 activity (EC₅₀ = 3.2 μM) while 5h showed anti-HIV-1 activity (EC₅₀ = 3.8 μM) with no toxicity at all in primary human lymphocytes, CEM and VERO cells.     

Synthesis,Analysis, and Acute Toxicity of 9-(2-diethylaminoethyl)-2-phenylimidazo[1,2-α]benzimidazole Dinitrate

Pharmaceutical Chemistry Journal - The key synthetic stage (cyclization) of 9-(2-diethylaminoethyl)-2-phenylimidazo[1,2-α]benzimidazole dinitrate, which possesses antiulcer activity, was...