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861.
The antitumor activity of dihydroxyanthracenediones such as mitoxantrone on a panel of cancer cell lines during the last 30 years, led investigators to synthesize thousands of anthracycline analogs and test their cytotoxicity to identify compounds superior to the parent drugs in terms of increased therapeutic effectiveness, reduced toxicity or both. To achieve this, new synthesized congeners either have different side arms or have extra rings on their skeletons. Following these studies, we proposed total synthesis of 2-amino-N-[4-(2-amino-3-hydroxy-propionylamino)-9,10-dioxo-9,10-dihydroanthracene-1-yl]-3-hydroxy-propionamide (V) and 6-amino-hexanoic acid [4-(5-amino-pentanoylamino)-9,10-dioxo-9,10-dihydro-anthracen-1-yl]-amide (VI). Acetylation of 1,4-diaminobenzene using acetyl chloride and reaction with phthalic anhydride under a Friedel-Crafts reaction and then cyclization gave 1, 4-diamino-anthraquinone. This compound was reacted with two amino acids (L-serine and 6-amino hexanoic acid) in their ester forms, using ethyl chloroformate as a coupling agent. Hydrolyzing esterified compounds gave their amino substituted derivatives. These compounds with diamine side arms are supposed to provide better intercalation with DNA. Synthesized novel ametantrone derivatives were tested against a panel of cancer cells (KB, Hela, MDA-MB-468 and K562), using MTT assay. The results showed that tested compounds inhibited the growth of cancer cells at micromolar concentrations. However, compound (VI) was more cytotoxic than compound (V) probably because of its longer side chains and better intercalation with DNA. 相似文献
862.
A simple, rapid and sensitive high-performance liquid chromatographic method for the determination of buspirone in plasma was developed. Buspirone was isolated from plasma using protein precipitation by acetonitrile and the recovery was complete. Citalopram was used as internal standard. The chromatographic conditions were as follows: analytical 125 x 4 mm, i.d. Nucleosil C18 column (5 microm particle size), mobile phase consisting of sodium dihydrogen phosphate buffer/acetonitrile (60:40, v/v) adjusted to pH 5.5 at a flow rate of 1.0 ml min(-1), UV detection at 235 nm. The quantification limit for buspirone in plasma was 0.5 ng ml(-1).The calibration curve was linear over the concentration range 0.5-10 ng ml(-1). The inter- and intra-day assay coefficients of variation were found to be less than 8%. The present validated method was successfully used for bioequivalence studies of buspirone in human subjects. 相似文献
863.
Synthesis of new Palladium(II) and Ruthenium(II) complexes of the type, [Pd(L)Cl(2)] and [Ru(eta(4)-C(8)H(12))(L)Cl(2)] [where, L = thiosemicarbazones derived from 5-nitrothiophene-2-carboxaldehyde and cycloalkylaminothiocarbonyl hydrazines] have been isolated by the reaction of [Pd(DMSO)(2)Cl(2)] and [Ru(eta(4)-C(8)H(12))(CH(3)CN)(2)Cl(2)] with 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones. The spectral data revealed that the thiosemicarbazones act as bidentate ligands, making use of thionic sulphur and the azomethine nitrogen atom for coordination to the central metal ion. Microdilution method was used for the assessment of antiamoebic activity of all the compounds against HK-9 strain of Entamoeba histolytica. Among all the thiosemicarbazones, 5-NT-4-BPTSCN (3) showed significant antiamoebic activity (IC(50) - 2.56 microM). Enhancement of antiamoebic activity resulted by introducing palladium and ruthenium metals in the thiosemicarbazone moiety. All the Pd(II) and Ru(II) complexes of 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones were found more active then their respective ligands. The complexes 1a-4a, 1b and 3b showed antiamoebic activity. 相似文献
864.
865.
Samdani AJ 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2004,14(10):626-627
Autosomal recessive ectodermal dysplasia with acanthosis nigricans is termed Lelis' syndrome. It is a rare condition and one case is described with overall clinical, dermatological and dental findings. 相似文献
866.
867.
The aim of the present study was to investigate the relationship between noncarious cervical lesions (NCCL) and dental premature contacts (PC). Following examination of 1,974 teeth from 77 patients referred to the Department of Oral Medicine, Faculty of Dentistry, Mashad University of Medical Science, Iran, a total of 167 teeth were identified to have the criteria set for noncarious cervical lesions (regarded as NCCL group). Also, 167 teeth exhibiting no such lesions were selected randomly from the same population (regarded as control group). The results indicated that within the NCCL group, the frequency of noncarious cervical lesions differed significantly among the various teeth; the first premolar teeth showed the greatest number of cervical lesions, followed by the canine teeth, and the second molar teeth had the least number of lesions. A similar trend was detected in the total number of premature contacts among the seven types of teeth. The results revealed a highly significant and positive correlation between the incidence of NCCL and the PC. The NCCL group and the control group differed significantly in the number of premature contacts in centric relation (CR) and working side, but not in balancing and protrusion. 相似文献
868.
Khan NU Ahmed S Wagner P Rumley RL Movahed A 《The international journal of cardiovascular imaging》2004,20(6):477-481
AIDS has resulted in a significant increase in the incidence of both primary and secondary cardiac lymphomas. Prognosis of HIV associate cardiac non-Hodgkins lymphoma is poor with very limited survival. Many cases of cardiac involvement in lymphoma remain undetected secondary to non-specific symptoms. Chemotherapy may produce remission in some cases. We report two cases of cardiac involvement with B-cell lymphoma. The first patient had a history of AIDS while the second had no evidence of HIV infection. 相似文献
869.
870.