Synthesis and in vitro cytotoxicity evaluation of novel naphthindolizinedione derivatives

Novel 6,11-dioxo-6,11-dihydro-benzo[f]pyrido[1,2-a]indole-12-carboxamide derivatives and the corresponding 7,10-dihydroxy analogues were designed in accordance with Moore's and Pindur's theory and synthesized based on the structural similarity with known antitumour agents such as ellipticine, daunorubicin, mitoxantrone and 9-aminoacridine-4 carboxamide derivatives. These compounds, including structural variations of the amide side chain, were evaluated in the NCI panel of human tumour cell lines, from which 6,11-dioxo-6,11-dihydro-benzo[f]pyrido[1,2-a]indole-(2-dimethylamino-ethyl)-12-carboxamide 11a was found to be the most potent agent within the series. It showed good selectivity towards leukaemia, colon and renal cancer cell lines, with significant GI50 values, from lower than 10 nM to 0.2 microM. Moreover, its cytotoxicity against the adriamicine-resistant breast tumour cell line at a concentration lower than 1 microM turned out to be higher than the values using the clinical anticancer agents, daunorubicin and mitoxantrone.     

Synthesis and in vitro protozoocidal evaluation of novel diazabicyclic tropolone derivatives

The synthesis and in vitro antiparasitic activity of twenty-seven novel diazabicycles based on tropolone ethers is presented. The compounds can be readily prepared by means of a high-yielding hetero Diels-Alder reaction using simple and readily available starting materials. Several of the new diazabicycles have in vitro activities against Trypanosoma cruzi, Leishmania donovani, Trypanosoma brucei rhodesiense, and chloroquine-resistant Plasmodium falciparum that are comparable or superior to those of currently employed protozoocidal agents.     

Synthesis and antimicrobial activity of some novel 2-(p-substituted-phenyl)-5-substituted-carbonylaminobenzoxazoles

A series of 2-(p-substituted-phenyl)-5-substituted-carbonylamino benzoxazole derivatives (5-22) was synthesized and their antimicrobial activities determined in comparison to several control drugs. The synthesized compounds were tested in vitro against Staphylococcus aureus, Streptococcus faecalis and Bacillus subtilis as Gram-positive, Pseudomonas aeruginosa and Escherichia coli as Gram-negative bacteria and the yeast Candida albicans. Microbiological results showed that the compounds possessed a diffuse spectrum of antibacterial activity against these microorganisms. Compound 9 which bears a phenylacetamido moiety at position 5 and a 4-fluorophenyl group at the 2-position of benzoxazole ring was the most active derivative against S. aureus, S. faecalis and P. aeruginosa with a MIC value of 12.5 microg/ml. Compound 11 provided higher potency than the other tested compounds against B. subtilis at a MIC value of 12.5 microg/ml. Compounds 5-22 showed antifungal activity against C. albicans with MIC values between 50 and 12.5 microg/ml.     

In vitro microbiological evaluation of TEI-1194 and TEI-2012, novel antipseudomonal semisynthetic penicillins.

TEI-1194, sodium 6-[D-(-)-alpha-(coumarin-3-carboxamide)-phenylacetamide] penicillanate and TEI-2012, sodium 6[D-(-)alpha-(8-hydroxy-coumarin-3-carboxamide)-phenylacetamide] penicillanate are new semisynthetic penicillin derivatives both possessing a broad spectrum of in vitro antibacterial activities. Minimal inhibitory concentrations of both agents were compared with carbenicillin. TEI-1194 and TEI-2012 were clearly found to have more potent activities especially against Pseudomonas aeruginosa than carbenicillin. At a concentration at 6.25 micrograms/ml, 85 approximately 90% of a total of 50 strains of clinically isolated P. aeruginosa were inhibited by TEI-1194 and TEI-2012, whereas carbenicillin had no effect. Evaluation of the antibacterial activity against a series of mutants producing different levels of beta-lactamases and test of the susceptibilities to some beta-lactamases demonstrated that TEI-1194 and TEI-2012 had low susceptibility to various cephalosporinases. However, both compounds were susceptible to penicillinase from Klebsiella pneumoniae H-2 at a rate of about 15% of penicillin-G taking its absolute rate as 100.     

Synthesis and antimicrobial evaluation of novel platensimycin analogues

Since the isolation of the natural products platensimycin and platencin as new antibiotic lead structures, several total syntheses as well as syntheses of derivatives have been developed. Most of these approaches are very laborious and the target molecules are often produced in only poor overall yields. The following approach describes the synthesis of rather simple platensimycin analogues focussing on some structure elements that have previously been identified as being essential for binding to the Fab F enzyme in fatty acid biosynthesis. Two of the new analogues show significant antimicrobial activities.     

Potential antimicrobial agents-I: Structural modifications and antimicrobial activity of some isatin derivatives

New isatin-3-isonicotinylhydrazones, isatinazine and its Mannich bases and spiro (indoline-3, 2'-thiadiazoline)-2-one have been synthesized. These compounds have been screened for their antibacterial activity against the Gram-positive and Gram-negative bacteria.     

5-氨基-8-甲氧基喹诺酮类化合物的合成及体内外抗菌作用

通过5-氨基-1-环丙基-6,7-二氟-8-甲氧基-1,4-二氢-4-氧代喹啉-3-羧酸与不同的环胺进行缩合反应,合成了5个未见文献报道的5-氨基-8-甲氧基喹诺酮类化合物。它们的结构均经核磁共振氢谱和高分辨质谱所确证。用环丙沙星及加替沙星作对照,测定了它们的体外抗菌活性,结果表明它们具有广谱活性,其中化合物5、7和9活性十分明显地优于对照药;化合物5和9进一步评价了其体内活性,结果表明化合物5和9分别比对照药加替沙星和莫西沙星具有更优秀的体内活性,值得深入研究。     

取代咪唑肟醚衍生物的合成

以抗真菌药物奥苷康唑为导化合物，设计并合成了１６个新的不同取代苄基结构的咪唑肟醚类化合物，期望找到更有效，更广谱的抗真菌化合物，化合物的结构经元素分析，ＨＮＭＲ及ＩＲ光谱所证实。     

Studies on the synthesis of some new substituted benzylamino and phenyl-acrylamido-methyl flavone derivatives

The synthesis and biological activity of a new series of 2-{3-[substituted benzylamino-methyl)-phenyl]-4H-benzopyrane-4-one (IVa-e) and N-substituted benzyl-N-[3-(4-oxo-4H-benzopyrane-2-yl)benzyl]-3-phenyl-acrylamide (Va-e) derivatives are reported. The synthesized compounds were tested in vitro for antifungal and antibacterial activities. Compound IVa showed the best antifungal activity compared with miconazole (CAS 22916-47-8). Compound IVc indicated the best antibacterial activity compared with the control drug ampicillin (CAS 69-53-4).