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1.
Growth-inhibitory activities of selected natural benzofurans (4-9), trans-cinnamic acid derivatives (10-13), chromene compounds (14 and 16), and some semisynthetic derivatives were determined in last instar larvae of Tenebrio molitor via topical administration in Me2CO. The most inhibitory of the tested compounds were 3-gamma, gamma-dimethylallyl-p-coumaric acid (10) and the benzofuran derivative 12-(p-cumaroyloxy)-tremetone (5), the former compound acting on the pupae and the latter on the last instar larvae. Several developmental deficiencies were observed, and some structure-activity relationships are discussed.  相似文献   

2.
Quinazolinone derivatives I and their methyl esters were synthesized and evaluated as nonclassical lipophilic inhibitors of thymidylate synthase. Compounds Ib and Ic containing OH and CO2H as R substituents, respectively, were most effective, indicating that hydrogen bonding may contribute to the increased inhibitory activity. These compounds further showed high cytotoxic activity against tumor cells in culture.  相似文献   

3.
Fifty-four 1-carbamoyl-5-fluorouracils were synthesized from 5-fluorouracil and isocyanate or amine. Antitumor activity was tested in the L-1210 tumor system, and 11 compounds gave better values of therapeutic ratio than HCFU (1-hexylcarbamoyl-5-fluorouracil). 1-(4-Methoxycyclohexylcarbamoyl)-5-fluorouracil gave the best result.  相似文献   

4.
A novel series of indole and benzimidazole derivatives were synthesized and evaluated for their inhibitory activity of rat prostatic 5alpha-reductase. Among these compounds, 4-?2-[1-(4,4'-dipropylbenzhydryl)indole-5-carboxamido]phenoxy?buty ric acid (15) and its benzimidazole analogue 25 showed potent inhibitory activities for rat prostatic 5alpha-reductase (IC50 values of 9.6+/-1.0 and 13+/-1.5 nM, respectively), with the potency very close to that of finasteride. Compound 30, in which the moiety between the benzene ring and amide bond was replaced by quinolin-4-one ring, showed almost equipotent activity (IC50= 19+/-6.2nM) with the correspondent amide derivative 13. This result was consistent with the previous observation that the coplanarity of this moiety might contribute to the potent inhibitory activity.  相似文献   

5.
The natural immunity status in different age groups was investigated. The positive rate of HI antibody under the age of 4 was less than 25%. The natural immunity level increased gradually with age and the positive rate of the antibody reached 80% among the group aged 13-25. Rate of seroconversion was 100% in any age group one month after immunization, and GMT rose from 13.33 to 243.16. It was suggested that immunogenicity of domestic attenuated live rubella vaccine BRD II was satisfactory. For the population with positive-antibody before immunization, the total GMT rose from 189.59 to 259.00 after vaccination and the difference between immunization before and after was highly significant. According to the above result, we suggested that the vaccination strategy for rubella among young children and women of child-bearing age should be implemented.  相似文献   

6.
The metabolism of steroid hormones in the medial basal hypothalamus (MBH) is known to play a critical role in neural development, the modulation of neuroendocrine function and regulating sexual behavior. While the important biological functions of the aromatase enzyme are well established, the importance of brain 5alpha-reductase has been revealed and elucidated only in the last few years. The distribution and regulation of brain aromatase and 5alpha-reductase enzyme activities have been investigated for the most part in male rats. Therefore, in the present study, MBH aromatase cytochrome P450 and 5alpha-reductase activities were characterized in pregnant and female rats during postnatal development under various hormonal conditions. MBH aromatase activity was determined in each tissue sample using the 'tritiated water release' assay, whereas, the 5alpha-reductase rates were determined by thin layer chromatography and scintillation counting of the isolated 5alpha-metabolites. Both activities were highest in infantile animals, then declined with increasing postnatal age; whereas, in aged non-cycling or ovariectomized/adrenalectomized (Ovx/Adx) rats high rates of androgen metabolism were seen in MBH tissue. No significant alterations in MBH aromatase were observed when the 5alpha-reductase pathway was blocked in pregnant animals during late gestation with a known 5alpha-reductase inhibitor (Proscar). However, plasma estradiol levels were significantly increased in the Proscar-treated animals. These results indicate that: 1) the decreasing MBH aromatase and 5alpha-reductase profile (in infantile to adult cycling animals) is developmentally regulated, 2) evidently, there is a divergent regulatory mechanism controlling MBH aromatase versus 5alpha-reductase in aged animals where the aromatase activity increased in aged non-cycling and Ovx/Adx rats while 5alpha-reductase rates remained at moderate levels and, 3) apparently, the 5alpha-reductase pathway is not involved in regulating MBH aromatase activity during late pregnancy.  相似文献   

7.
Discoid lupus erythematosus (DLE) is an uncommon disease in childhood. We present two patients initially diagnosed as impetigo and photosensitive eczema with impetigo, respectively, who failed to respond to topical and systemic antistaphylococcal agents and in whom a diagnosis of discoid lupus erythematosus subsequently became apparent.  相似文献   

8.
Synthesis of benzanilide derivatives which have dual alpha 1-adrenoceptor antagonistic action and steroid 5 alpha-reductase inhibitory activity and their structure-activity relationships is described.  相似文献   

9.
Nine 1,2,5-trisubstituted benzimidazole derivatives were prepared and their structure have been elucidated by IR, NMR spectral data and elemental analyses. Analgesic activity of the compounds prepared was investigated in mice by modified KOSTER test. Anti-inflammatory activity of these compounds was investigated by a carregeenan-induced hind paw edema model in mice. Their antibacterial activities were examined against S. aureus, E. faecalis, E. coli, P. aeruginosa, and antifungal activity against three kinds of yeast-like fungi (C. albicans, C. parapsilosis, C. stellatoidea).  相似文献   

10.
13-Dehydro derivatives of prostaglandin E1, E2, E3, F1 alpha and F2 alpha were synthesized. Compared with natural prostaglandins, 13-dehydro analogues were found to exhibit more potent inhibitory activity against human platelet aggregation and relaxation of guinea-pig isolated trachea, while they showed less potent activity of contraction of guinea-pig isolated ileum.  相似文献   

11.
An active site model of 5 alpha-reductase type 2 isoenzyme on an "active-analog approach" and based on 4-azasteroidal inhibitors has been constructed to evaluate the effects on the inhibitory potency of substituents on the steroid A ring. This model has proven able to predict the potential inhibitory activity of 19-nor-10-azasteroid and 6-azasteroid compounds. A model for the evaluation of clinical efficacy of an inhibitor, based on in vitro data, has also been developed and applied to finasteride. This inhibitory potency evaluation of finasteride in human scalp homogenates, plus pharmacokinetic data, allows the calculation of a theoretical in situ inhibition value for human scalp. From the IC50 curve of finasteride in scalp homogenates, it is possible to calculate that for an inhibition level similar to that obtained in prostate with 5 mg of finasteride, the necessary plasma concentration of the drug is 1 microM, a level obtained after the acute administration of 50 mg of finasteride.  相似文献   

12.
In search for new antitumor agents, twelve 6-aziridinylbenzimidazole derivatives were synthesized and their cytotoxicities were tested against three cancer cell lines (mouse lymphocytic leukemia P388 and B16, and human gastric carcinoma SNU-16). From 4-amino-3-nitrotoluene as the starting material, 2-(acetoxymethyl)benzimidazoles (5a-d) were obtained by Phillips reaction. These benzimidazoles were then reacted with Fremy's salt to give a mixture of three 2-(acetoxymethyl) (8a-c) and four 2-(hydroxymethyl)benzimidazole-4,7-diones (9a-d). Addition of these quinones with aziridine afforded 6-aziridinyl-2-(acetoxymethyl) (10a-c) and 6-aziridinyl-2-(hydroxymethyl)benzimidazole-4,7-diones (11a-d). Utilizing 2-(hydroxymethyl)benzimidazole-4,7-diones (9b,d), esters 10d and 13e-h were prepared by the sequential reactions of esterification and addition. The synthesized compounds show potent cytotoxicity against all of three cell lines tested. The cytotoxicities of 10a-d or 11a-d against SNU-16 were superior to those of 13e-h, and were equal to or slightly higher than that of mitomycin C. Compounds 11a-d were slightly more cytotoxic than 10a-d in all cell lines tested.  相似文献   

13.
We report syntheses of DHPA analogs, e.g., 9-(3-formyl-2,3-dihydroxypropyl)adenine (FDHPA) and 9-(3-formyl-2,3-dihydroxypropyl)hypoxanthine (FDHPI). Among these DHPA analogs, FDHPA behaved as an irreversible inactivator of human recombinant SAH hydrolase.  相似文献   

14.
5 alpha-Reductase deficiency is a rare autosomal recessive disorder of defective virilization in karyotypic males due to reduced conversion of testosterone to dihydrotestosterone. The gene encoding the affected 5 alpha-reductase type 2 enzyme has recently been cloned, and mutations within the coding region have been discovered as the cause of this disease. We address the possibility of a rapid nonradioactive molecular genetic screening technique for initial diagnosis and report different point mutations in this gene in eight unrelated patients with clinical features of 5 alpha-reductase deficiency. For molecular genetic analysis, DNA from peripheral blood leukocytes was studied. The coding region of the 5 alpha-reductase type 2 gene was characterized by exon-specific PCR amplification, nonradioactive single strand conformation analysis, and direct sequencing. In seven patients, homozygous point mutations were identified (Leu55-Gln, delta Met157, Gly196-Ser, Arg227-Gln, Ala228-Thr, and His231-Arg). One individual was a compound heterozygote carrier of two mutations (Ile112-Asn and Gln126-Arg). We conclude that molecular genetic characterization of point mutations in the 5 alpha-reductase type 2 gene may be used as an additional valuable procedure for the diagnosis of this disorder.  相似文献   

15.
OBJECTIVE: To evaluate the effects of long-term administration of finasteride on hirsutism score, basal gonadotropin, and androgen secretion in women with idiopathic hirsutism. DESIGN: Randomized single-blinded study. PATIENTS: Eighteen patients with moderate-severe hirsutism were recruited for the study. INTERVENTIONS: Nine hirsute patients received 7.5 mg/d oral finasteride for a period of 9 months whereas the other nine were treated with placebo. Hirsutism score, serum basal gonadotropin, androgens, estrogen, and sex hormone-binding globulin (SHBG) levels were evaluated in all patients before treatment and every 3 months during treatment. RESULTS: After 6 and 9 months of treatment, the hirsutism score improved significantly in the patients receiving finasteride, whereas no significant modifications were observed in patients treated with placebo. The side effects observed were headache and depression of modest entity during the 1st month of treatments, whereas libido did not change. Serum levels of LH, FSH, androstenedione, unbound T, DHEAS, E2, 17 alpha-hydroxyprogesterone, and SHBG did not change during therapy. Hirsute patients treated with finasteride exhibited a marked decrease of dihydrotestosterone and a significant increase of T serum levels from the 3rd and 6th months of treatment, respectively. CONCLUSION: Finasteride decreased the hirsutism score of patients affected by idiopathic hirsutism with few side effects during treatment. No modification of libido was observed.  相似文献   

16.
A number of sulfur-containing amide-carboxylic acid derivatives were synthesized and tested for cholecystokinin A (CCK-A) receptor inhibitory activity in order to study structure-activity relationships. Significant CCK-A receptor inhibitory activities were found in only two series, that is, sulfoxide-carboxylic acid derivatives (9) and sulfone-carboxylic acid derivatives (10). As the most preferred compound, 5-(3,4-dichlorophenylsulfonyl)-4-(N,N-dipentylcarbamoyl)pent anoic acid (10n) was selected.  相似文献   

17.
A series of 9-(N4-substituted acetaldehyde thiosemicarbazone) adenines were synthesized and evaluated for antiherpes virus activity. Compounds 4a-l were prepared by condensation of 9-(acetaldehyde) adenine(6) and the corresponding N4-substituted thiosemicarbazides (10). The antiviral effects of all compounds 4a-l were tested in vitro in primary rabbit kidney cell cultures infected with herpes simplex virus type 1 (HSV-1) and varicella-herpes zoster virus (VZV), and in primary human embryo cell cultures infected with herpes simplex virus type 2 (HSV-2). The results showed that the minimum inhibitory concentrations (MIC) of 4e and 4f for HSV-1 and VZV were 20, 40, 20 and 20 micrograms.ml-1, respectively, and other compounds were 200 micrograms.ml-1. For HSV-2, the MIC of all tested compounds were 300 micrograms.ml-1. We also evaluated the antiherpetic effect of 4e (and 4f) by combination with acyclovir (ACV) in the ratio of 1:1 in vitro. The MIC of the combined compounds were 2 micrograms.ml-1 for 4e and 6 micrograms.ml-1 for 4f, while their minimum cytotoxicities (MCC) in the cell were markedly reduced compared with the individual compounds.  相似文献   

18.
The enzyme steroid 5 alpha-reductase (EC 1.3.99.5) is a component of an intercellular signaling pathway that determines cell fate in the primordium of the mammalian reproductive tract. During male phenotypic sexual differentiation, the dihydrotestosterone product of this enzyme binds to the androgen receptor and initiates development of the external genitalia and prostate. Genes encoding two isozymes of steroid 5 alpha-reductase with different biochemical properties and tissue distributions have recently been isolated. In the current study, we utilize in situ hybridization analysis to determine cell-type-specific expression patterns of the 5 alpha-reductase isozyme mRNAs in two androgen target tissues (regenerating ventral prostate and epididymis) and a peripheral tissue (liver). In regenerating ventral prostate, the type 1 mRNA is expressed in basal epithelial cells whereas expression of the type 2 mRNA is largely confined to stromal cells. These results were confirmed by immunohistochemical analysis and are consistent with distinct roles played by the isozymes in the prostate. In the epididymis, both 5 alpha-reductase isozyme mRNAs are expressed in epithelial cells. Only the type 1 mRNA is present in the liver. This mRNA is distributed in a striking spatial gradient extending from hepatocytes surrounding the portal triad (high expression) to those surrounding the central vein (low to absent expression). These findings demonstrate cell-type-specific expression of the steroid 5 alpha-reductase isozymes and underscore their distinct and overlapping functions in androgen physiology.  相似文献   

19.
Phospholipase A2 is an enzyme which hydrolyzes the sn-2 position of certain cellular phospholipids. The liberated lysophospholipid and arachidonic acid are precursors in the biosynthesis of various biologically active products. As human nonpancreatic sPLA2 is present in high levels in the blood of patients in several pathological conditions, the potent sPLA2 inhibitors have been suggested to be useful drugs. Here we describe the synthesis, structure-activity relationship, and inhibitory activities of indolizine and indene derivatives. 1-(Carbamoylmethyl)indolizine derivatives and 1-oxamoylindolizine derivatives exhibited very potent inhibitory activity. The former was unstable to air oxidation, but the latter exhibited an improvement both in stability and in potency. Some compounds approached the stoichiometric limit of the chromogenic assay.  相似文献   

20.
PNU 157706 is a novel dual inhibitor of 5alpha-reductase (5alpha-R), the enzyme responsible for the conversion of testosterone (T) to 5alpha-dihydrotestosterone (DHT). Tested on a crude preparation of human or rat prostatic 5alpha-R, PNU 157706 caused enzyme inhibition with IC50 values of 20 and 34 nM, respectively, compared to the values of 32 and 58 nM shown by finasteride. Furthermore, PNU 157706 was highly potent in inhibiting human recombinant 5alpha-R type I and II isozymes, showing IC50 values of 3.9 and 1.8 nM and, therefore, it was several folds more potent than finasteride (IC50 values of 313 and 11.3 nM), particularly on the type I isozyme. PNU 157706 was shown to have no binding affinity for the rat prostate androgen receptor (RBA 0.009% that of DHT). In adult male rats, a single oral dose of 10 mg/kg of PNU 157706 caused a marked and longer lasting reduction of prostatic DHT than did finasteride (at 24 h inhibition by 89 and 47%, respectively). In prepubertal, T- or DHT-implanted castrated rats, PNU 157706, given orally for 7 days at the dose of 10 mg/kg/day, markedly reduced ventral prostate weight in T- but not in DHT-implanted animals, thus showing to be devoid of any anti-androgen activity. In adult rats treated orally for 28 days, PNU 157706 resulted markedly more potent (16-fold) than finasteride in reducing prostate weight, the ED50 values being 0.12 and 1.9 mg/kg/day, respectively. These results indicate that PNU 157706 is a promising, potent inhibitor of both type II and I human 5alpha-R with a very marked antiprostatic effect in the rat.  相似文献   

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