Design, Synthesis, and Biological Activity of 4-[(4-Cyano-2-arylbenzyloxy)-(3-methyl-3H-imidazol-4-yl)methyl]benzonitriles as Potent and Selective Farnesyltransferase Inhibitors

A novel series of 4-[(4-cyano-2-arylbenzyloxy)-(3-methyl-3H-imidazol-4-yl)methyl]benzonitriles have been synthesized as selective farnesyltransferase inhibitors using structure-based design. X-ray cocrystal structures of compound 20-FTase-HFP and A313326-FTase-HFP confirmed our initial design. The decreased interaction between the aryl groups and Ser 48 in GGTase-I binding site could be one possible reason to explain the improved selectivity for this new series of FTase inhibitors. Medicinal chemistry efforts led to the discovery of compound 64 with potent cellular activity (EC(50) = 3.5 nM) and outstanding pharmacokinetic profiles in dog (96% bioavailable, 18.4 h oral t(1/2), and 0.19 L/(h x kg) plasma clearance).

Reagents for Astatination of Biomolecules: Comparison of the in Vivo Distribution and Stability of Some Radioiodinated/Astatinated Benzamidyl and nido-Carboranyl Compounds

An investigation has been conducted to assess the in vivo stability of a series of astatinated benzamides and astatinated nido-carborane compounds in mice. It was hypothesized that the higher bond strength of boron-astatine bonds in the nido-carboranes might provide increased stability toward in vivo deastatination. Four tri-n-butylstannylbenzamides were prepared for radiohalogenation and evaluation in vivo. Those compounds were N-propyl-4-(tri-n-butylstannyl)benzamide 1a, N-propyl-3-(tri-n-butylstannyl)benzamide 2a, ethyl 4-tri-n-butylstannylhippurate 3a, and 4-tri-n-butylstannyl-hippuric acid 4a. Seven mono-nido-carboranyl derivatives were prepared for radiohalogenation and in vivo evaluation. Four of the seven mono-carboranyl derivatives (5a, 6a, 7a, 13a) contained a 3-(nido-carboranyl)propionamide functionality, and the remaining compounds (8a, 8g, 10a) contained a 4-(nido-carboranyl)aniline functionality. Two additional derivatives (11a, 12a) were prepared that contained bis-(nido-carboranylmethyl)benzene moieties (also referred to as Venus flytrap complexes (VFCs). All benzamide and nido-carborane compounds underwent facile iodination and radiohalogenation, except a 4-(nido-carboranyl)aniline derivative, 8a. Iodination of 8a resulted in a mixture, of which the desired iodinated product was a minor component. Therefore, radiohalogenation was not attempted. It is believed that the mixture of products is due to the presence of a thiourea bond. Previous studies have shown that thiourea bonds can interfere with halogenation reactions. In vivo comparisons of the compounds were conducted by co-injection of dual labeled (125/131I and 211At) compounds. Tissue distribution data were obtained at 1 and 4 h postinjection of the radiolabeled compounds, as that was sufficient to determine if astatine was being released. Stability of the astatinated compound was assessed by the difference in concentration of radioiodine and astatine in lung and spleen. All of the benzamides were found to undergo rapid deastatination in vivo. The nido-carborane derivatives appeared to be slightly more stable to in vivo deastatination; however, they had long blood residence times. The surprising finding was that the VFC derivatives did not release 211At in vivo, even though they rapidly localized to liver. This finding provides encouragement that stable conjugates of 211At may be attained if appropriate modifications of the VFC can be made to redirect their excretion through the renal system.

Zn2+-Chelating Motif-Tethered Short-Chain Fatty Acids as a Novel Class of Histone Deacetylase Inhibitors

Among various classes of histone deacetylase (HDAC) inhibitors, short-chain fatty acids exhibit the least potency, with IC(50) in the millimolar range. We rationalized that this weak potency was, in part, attributable to their inability to access the zinc cation in the HDAC active-site pocket, which is pivotal to the deacetylation catalysis. We thus explored the structural optimization of valproate, butyrate, phenylacetate, and phenylbutyrate by coupling them with Zn(2+)-chelating motifs (hydroxamic acid and o-phenylenediamine) through aromatic omega-amino acid linkers. This strategy has led to a novel class of Zn(2+)-chelating, motif-tethered, short-chain fatty acids that exhibited varying degrees of HDAC inhibitory potency. One hydroxamate-tethered phenylbutyrate compound, N-hydroxy-4-(4-phenylbutyrylamino)benzamide (HTPB), displayed nanomolar potency in inhibiting HDAC activity. Exposure of several cancer cell lines to HTPB at the submicromolar level showed reduced cell proliferation accompanied by histone hyperacetylation and elevated p21(WAF/CIP1) expression, which are hallmark features associated with intracellular HDAC inhibition.

Synthesis and affinity of a possible byproduct of electrophilic radiolabeling of [123I]IBZM

The iodobenzamide neuroleptic analogue (S)-N-(1-ethylpyrrolidin-2-ylmethyl)-2-hydroxy-5-iodo-6-methoxybenzamide (5-IBZM) was synthesized stereospecifically and its pharmacological properties were compared with the 3-iodo isomer (IBZM) used for imaging D(2) receptors in vivo. The isomer 5-IBZM had 100-fold lower affinity than IBZM and migrated with similar retention time as the byproduct formed during electrophilic iodination of BZM.

Diaryldimethylpiperazine ligands with μ- and δ-opioid receptor affinity: Synthesis of (+)-4-[(αR)-α-(4-allyl-(2S,5S)-dimethylpiperazin-1-yl)-(3-hydroxyphenyl)methyl]-N-ethyl-N-phenylbenzamide and (−)-4-[(αR)-α-(2S,5S)-dimethylpiperazin-1-yl)-(3-hydroxyphenyl)methyl]-N-ethyl-N-phenylbenzamide

We have explored the synthesis of compounds that have good affinity for both mu- and delta-opioid receptors from the (alphaR,2S,5S) class of diaryldimethylpiperazines. These non-selective compounds were related to opioids that have been found to interact selectively with mu- or delta-opioid receptors as agonists or antagonists. In our initial survey, we found two compounds, (+)-4-[(alphaR)-alpha-(4-allyl-(2S,5S)-dimethylpiperazin-1-yl)-(3-hydroxyphenyl)methyl]-N-ethyl-N-phenylbenzamide (14) and its N-H relative, (-)-4-[(alphaR)-alpha-(2S,5S)-dimethylpiperazin-1-yl)-(3-hydroxyphenyl)methyl]-N-ethyl-N-phenylbenzamide (15), that interacted with delta-receptors with good affinity, and, as we hoped, with much higher affinity at mu-receptors than SNC80. The relative configuration of the benzylic position in (+)-4-[(alphaR)-alpha-(4-allyl-(2S,5S)-dimethyl-1-piperazinyl)-(3-methoxyphenyl)methyl]-benzyl alcohol (10) was determined by X-ray crystallographic analysis of a crystal that was an unresolved twin. The absolute stereochemistry of that benzylic stereogenic center was unequivocally derived by the X-ray crystallographic analysis from the two other centers of asymmetry in the molecule that were known. Those were established from the synthesis via a dipeptide cyclo-L-Ala-L-Ala in which the absolute stereochemistry was established.

Stereocontrolled dopamine receptor binding and subtype selectivity of clebopride analogues synthesized from aspartic acid

Employing the achiral 4-aminopiperidine derivative clebopride as a lead compound, chiral analogues were developed displaying dopamine receptor binding profiles that proved to be strongly dependent on the stereochemistry. Compared to the D1 receptor, the test compounds showed high selectivity for the D2-like subtypes including D2(long), D2(short), D3 and D4. The highest D4 and D3 affinities were observed for the cis-3-amino-4-methylpyrrolidines 3e and the enantiomer ent3e resulting in K(i) values of 0.23 and 1.8 nM, respectively. The benzamides of type 3 and 5 were synthesized in enantiopure form starting from (S)-aspartic acid and its unnatural optical antipode.

Design and synthesis of orally active benzamide derivatives as potent serotonin 4 receptor agonist

A series of 4-amino-5-chloro-2-methoxy-N-(piperidin-4-ylmethyl)benzamide derivatives bearing an aralkylamino, alkylamino, benzoyl or phenylsulfonyl group at its side chain part at the 1-position on the piperidine ring was synthesized. They were evaluated for serotonin 4 (5-HT(4)) receptor agonist activity by testing their ability to contract the isolated guinea-pig ascending colon. 4-Amino-5-chloro-2-methoxy-N-[1-[5-(1-methylindol-3-ylcarbonylamino)pentyl]piperidin-4-ylmethyl]benzamide (1a, Y-34959) and its related compounds possessed favorable pharmacological profiles for gastrointestinal motility. Unfortunately, the compound 1a showed low bioavailability when given orally presumably due to its poor intestinal absorption rate. Replacement of the 1-methylindol-3-yl carbonylamino moiety of 1a with an aralkylamino (or alkylamino) group did not improve the intestinal absorption rate. Replacement of the 1-methylindol-3-ylcarbonylamino moiety with a benzoyl or phenylsulfonyl group increased the intestinal absorption rate compared with 1a. These compounds revealed good pharmacological profiles for gastrointestinal motility and were superior to 1a in oral bioavailability.

Stereoselective preparation of N-[(R,R)-(E)-1-(3,4-dichlorobenzyl)-3- (2-oxoazepan-3-yl)carbamoyl]allyl-N-methyl-3,5-bis(trifluoromethyl)benzamide, a potent and orally active dual neurokinin NK(1)/NK(2) receptor antagonist

In a program aimed at the development of neurokinin antagonists, N-[(R,R)-(E)-1-(3,4-dichlorobenzyl)-3-(2-oxoazepan-3-yl)carbamoyl]allyl-N-methyl-3,5-bis(trifluoromethyl)benzamide (1, DNK333) has been discovered as a potent and balanced neurokinin (tachykinin) NK(1)/NK(2) receptor antagonist. Enantiomerically pure (>99.5% ee) 1 can be prepared in 6 + 1 synthetic steps starting from commercially available optically active BOC-d-3,4-dichlorophenylalanine in an overall yield of ca. 25-30%. 1 showed potent affinities to cloned human NK(1) (pK(i) = 8.38) and NK(2) (pK(i) = 8.02) receptors. When 1 was compared to the other possible three diastereoisomers, it could be demonstrated that only the R,R-isomer (1) exhibits potent and balanced affinity for the cloned human NK(1) and NK(2) receptors. 1 exhibited favorable pharmacokinetic properties in guinea pigs following oral administration and demonstrated in vivo activity in pharmacological models of substance P- and neurokinin A (NKA)-induced bronchoconstriction in guinea pigs after intravenous and in squirrel monkeys after oral application.

Development of a water-soluble matrix metalloproteinase inhibitor as an intra-arterial infusion drug for prevention of restenosis after angioplasty

To prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) and/or stenting of atherosclerotic stenosed arteries, we designed and developed two water-soluble matrix metalloproteinases (MMPs) inhibitors. The first inhibitor was monomeric in type and was chemically synthesized by succinylation of the synthetic MMP inhibitor, N-hydroxy-5-hydroxy-2(S)-methyl-4(S)-(4-phenoxybenzoyl)aminopentanamide (ONO-M11-335). The second inhibitor was polymeric and was a radical copolymer of the vinyl derivative of ONO-M11-335 and a water-soluble monomer, N,N-dimethylacrylamide (DMAAm). For the second inhibitor, NMR analyses and UV-vis spectra measurements showed that the content of the ONO-M11-335 unit in the copolymers (M(n); ca. 10 000 and 20 000 by GPC measurements) was about 8 per molecule. The MMP inhibitors were all highly soluble in water, even under neutral pH. The succinylated derivative markedly inhibited MMP-2, MMP-9, and MMP-12 in vitro, as did ONO-M11-335. In contrast the copolymers, which can maintain effective plasma levels for extended periods by prevention of hepatic uptake, showed a ca. 100-fold reduced inhibition activity. Such water-soluble MMP inhibitors, developed in this study, may potentially be useful as an intra-arterial infusion drug for vascular injury.

4-Amino-2-(aryl)-butylbenzamides and Their conformationally constrained analogues. Potent antagonists of the human neurokinin-2 (NK(2)) receptor

A library, evaluating a range of piperazines, piperidines and acyclic amines, as replacements for the 4-hydroxy-4-phenylpiperidine moiety in lead (1b) was prepared. These efforts identified the 4-((N)-benzimidazolone)piperidine analogue (2a) which was further optimised using classical single-compound synthesis to yield the 3-((N)-morpholino)azetidine (2j). Conformationally constrained analogues of (2j), generally offered no potency advantage in this particular series.

[The new agent G-1724: synthesis and test on murine models of trichuriasis and trichinosis]

To search for new antihelminthics, the new compound N-[3-chloro-4-[(1-ethyl-2-benzimidazolyl) thio]phenyl]-2-hydroxy-3,5-dibromobenzamide (the agent G-1724) was synthesized and tested by using the models of trichocephaliasis (Trichocephalus muris) and trichinosis (Trichinella spiralis). The tests demonstrated that this agent had an nematocidal effect (71-78%).

Small molecule modulators of histone acetyltransferase p300

Histone acetyltransferases (HATs) are a group of enzymes that play a significant role in the regulation of gene expression. These enzymes covalently modify the N-terminal lysine residues of histones by the addition of acetyl groups from acetyl-CoA. Dysfunction of these enzymes is often associated with the manifestation of several diseases, predominantly cancer. Here we report that anacardic acid from cashew nut shell liquid is a potent inhibitor of p300 and p300/CBP-associated factor histone acetyltranferase activities. Although it does not affect DNA transcription, HAT-dependent transcription from a chromatin template was strongly inhibited by anacardic acid. Furthermore, we describe the design and synthesis of an amide derivative N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide (CTPB) using anacardic acid as a synthon, which remarkably activates p300 HAT activity but not that of p300/CBP-associated factor. Although CTPB does not affect DNA transcription, it enhances the p300 HAT-dependent transcriptional activation from in vitro assembled chromatin template. However, it has no effect on histone deacetylase activity. These compounds would be useful as biological switching molecules for probing into the role of p300 in transcriptional studies and may also be useful as new chemical entities for the development of anticancer drugs.

Inhibitory effects of N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines on nitric oxide generation in stimulated raw 264.7 macrophages

There has been great interest in reactive nitrogen intermediates and nitric oxide production in macrophages, particularly because of their contributory role in several pathophysiological conditions during acute and chronic inflammation. Several N-(substituted benzoylamino)-4-ethyl-1,2,3,6-tetrahydropyridines were previously synthesized as potential antiinflammatory agents. In the present study, the effects of four previously synthesized tetrahydropyridines (THPs) on cyclooxygenase (COX)-1 and COX-2 were screened and the effects of these compounds on lipopolysaccharide (LPS)-induced (2 micrograms/ml) nitric oxide and inducible nitric oxide synthase (iNOS) activity in RAW 264.7 macrophages were examined. 4-Bromo THP showed 9.4 microM of IC50 as the most potent derivative among the tested THPs followed by 4-nbuthyl, 4-fuoro, and 4-methyl THP with IC50 values of 30.9, 38.9 and 80.3 microM, respectively (indomethacin IC50 = 53.8 microM). None of the tested compounds showed cytotoxic effects to the RAW 264.7 macrophages. All of the tested THPs exhibited COX-1 and COX-2 nonselective inhibition. These results suggest that previously synthesized THP derivatives may have dual effects through inhibiting both COX and nitric oxide by inhibiting iNOS.

Synthesis of novel thrombin inhibitors. Use of ring-closing metathesis reactions for synthesis of P2 cyclopentene- and cyclohexenedicarboxylic acid derivatives

The thrombin inhibitory tripeptide d-Phe-Pro-Arg has been mimicked using either cyclopentenedicarboxylic derivatives or a cyclohexenedicarboxylic derivative as surrogate for the P2 proline. In the P3 position, tertiary amides were optimized as d-Phe P3 replacements. The P1 arginine was, in all compounds, substituted with the more rigid and biocompatible 4-aminomethylbenzamidine. One of the novel inhibitors was cocrystallized with alpha-thrombin and subjected to X-ray analysis. From analysis of the X-ray crystal structure, new ligands were designed leading to significantly improved binding affinity, the lead candidate exhibiting an in vitro IC(50) of 49 nM.

Benzamide derivatives as blockers of Kv1.3 ion channel

The voltage-gated potassium channel, Kv1.3, is present in human T-lymphocytes. Blockade of Kv1.3 results in T-cell depolarization, inhibition of T-cell activation, and attenuation of immune responses in vivo. A class of benzamide Kv1.3 channel inhibitors has been identified. The structure-activity relationship within this class of compounds in two functional assays, Rb_Kv and T-cell proliferation, is presented. In in vitro assays, trans isomers display moderate selectivity for binding to Kv1.3 over other Kv1.x channels present in human brain.

3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides: potent, non-peptidic agonists of both the micro and delta opioid receptors

Opioid analgesics with both micro and delta opioid receptor activation represent a new approach to the treatment of severe pain with an improved safety profile. Compounds with this profile may exhibit strong analgesic properties due to micro agonism, with a reduced side effect profile resulting from delta agonism. Replacing the p-diethylamide of the known potent delta opioid receptor selective agonist BW373U86 with a m-diethylamide resulted in a compound with agonist activity at both the micro and delta opioid receptors. Modifying the amide to an N-methyl-N-phenylamide increased agonist potency at both receptors. A series of 3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides have been made to explore the structure-activity relationship (SAR) around the N-methyl-N-phenylamide. Several potent agonists of both the micro and delta opioid receptors have been identified, including (+)-3-((alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-(4-fluorophenyl)-N-methylbenzamide (23), which has EC50 values of 0.67 and 1.1 nM at the micro (guinea pig ileum assay) and delta (mouse vas deferens assay) opioid receptors, respectively.

Total synthesis of (+)-benzastatin E via diastereoselective Grignard addition to 2-acylindoline

[reaction: see text] A stereoselective total synthesis of (+)-benzastatin E (1) is described. The synthesis involves a diastereoselective Grignard addition to 2-acylindoline 2, which is derived from commercially available (S)-2-indolinecarboxylic acid (3). The unknown absolute configuration of (+)-1 is determined as (9S,10R).

Optimizing limbic selective D2/D3 receptor occupancy by risperidone: a [123I]-epidepride SPET study

Selective action at limbic cortical dopamine D2-like receptors is a putative mechanism of atypical antipsychotic efficacy with few extrapyramidal side effects. Although risperidone is an atypical antipsychotic with high affinity for D2 receptors, low-dose risperidone treatment is effective without inducing extrapyramidal symptoms. The objective was to test the hypothesis that treatment with low-dose risperidone results in 'limbic selective' D2/D3 receptor blockade in vivo. Dynamic single photon emission tomography (SPET) sequences were obtained over 5 hours after injection of [123I]-epidepride (approximately 150 MBq), using a high-resolution triple-headed brain scanner (Marconi Prism 3000XP). Kinetic modelling was performed using the simplified reference region model to obtain binding potential values. Estimates of receptor occupancy were made relative to a normal volunteer control group (n = 5). Six patients treated with low-dose risperidone (mean = 2.6 mg) showed moderate levels of D2/D3 occupancy in striatum (49.9%), but higher levels of D2/D3 occupancy in thalamus (70.8%) and temporal cortex (75.2%). Occupancy values in striatum were significantly different from thalamus (F (1,4) = 26.3, p < 0.01) and from temporal cortex (F (1,4) = 53.4, p < 0.01). This is the first study to evaluate striatal and extrastriatal occupancy of risperidone. Low dose treatment with risperidone achieves a similar selectivity of limbic cortical over striatal D2/D3 receptor blockade to that of atypical antipsychotics with lower D2/D3 affinity such as clozapine, olanzapine and quetiapine. This finding is consistent with the relevance of 'limbic selective' D2/D3 receptor occupancy to the therapeutic efficacy of atypical antipsychotic drugs.

Synthesis and fungistatic activity of new groups of 2,4-dihydroxythiobenzoyl derivatives against phytopathogenic fungi

Twenty-six compounds, derivatives of amides, hydrazines, hydrazides, hydrazones, and semicarbazides, with a 2,4-dihydroxythiobenzoyl moiety, were synthesized from sulfinyl-bis(2,4-dihydroxythiobenzoyl). The compositions and chemical structures of these compounds were confirmed by IR, (1)H NMR, EI-MS, and elemental analysis. Antifungal properties of chemicals under in vitro conditions against five phytopathogenic fungi were estimated. In vivo studies against Erisiphe graminis were also carried out. The compounds N-substituted with an 2,4-dihydroxythiobenzamide group proved to be the most active. N-2-(1-Cinnamylbenzene ester)-2,4-dihydroxythiobenzamide, under in vitro conditions, showed activity at the level of 80-100% development of most pathogens at a concentration of 20 microg/mL and partially at a concentration of 200 microg/mL. For compounds with -HN-NH- or -NH-N= moiety, weak or no fungistatic properties were found at the concentrations studied.

Synthesis and anti-inflammatory activities of N-benzoylamino-1,2,3,6-tetrahydropyridine analogs

The anti-inflammatory activity of N-benzoylamino-1,2,3,6-tetrahydropyridine (Fig. 1) has been previously described. Further structural modification of 1 indicated that anti-inflammatory activities were greatly influenced by the position and nature of substituents on the tetrahydropyridine ring moiety. Analogs of 1 with benzyl group at position 4 of the tetrahydropyridine ring moiety and substituents on the benzene moiety were synthesized (9a-90). The effect of these substituents on pharmacological activity was screened in vivo using the carrageenan-induced paw edema assay in male Sprague-Dawley rats. Analogs with electron-donating substituents at position 4 and 2 of the benzene moiety 9f, 90 and 9d exhibited significant anti-inflammatory activities, similar to that observed for the reference compound, indomethacin. In summary, at an early stage of efforts to establish structure-activity relationship within this series, we found that 9f is a promising lead compound chosen for further investigation.

Structure-affinity relationship study on N-[4-(4-arylpiperazin-1-yl)butyl]arylcarboxamides as potent and selective dopamine D(3) receptor ligands

The benzamide PB12 (N-[2-[4-(4-chlorophenyl)piperazin-1-yl]ethyl]-3-methoxybenzamide) (1), already reported as potent and selective dopamine D(4) receptor ligand, has been modified searching for structural features that could lead to D(3) receptor affinity. Changes in the aromatic ring linked to N-1 piperazine ring led to the identification of 2-methoxyphenyl and 2,3-dichlorophenyl derivatives (compounds 6 and 13) displaying moderate D(3) affinity (K(i) = 145 and 31 nM, respectively). Intermediate alkyl chain elongation in compounds 1, 6, and 13 improved binding affinity for the D(3) receptor and decreased the D(4) affinity (compounds 18-26). Among these latter compounds, the N-[4-[4-(2,3-dichlorophenyl)piperazin-1-yl]butyl]-3-methoxybenzamide (19) was further modified with the replacement or of the 2,3-dichlorophenyl moiety (compounds 27-30) or of the 3-methoxyphenyl ring (compounds 31-41). In this way, we identified several high-affinity D(3) ligands (0.13 nM < K(i)'s < 4.97 nM) endowed with high selectivity over D(2), D(4), 5-HT(1A), and alpha(1) receptors. In addition, N-[4-[4-(2,3-dimethylphenyl)piperazin-1-yl]butyl]-3-methoxybenzamide (27) and N-[4-[4-(2,3-dichlorophenyl)piperazin-1-yl]butyl]-7-methoxy-2-benzofurancarboxamide (41) appear to be valuable candidates for positron emission tomography (PET) because of their affinity values, lipophilicity properties, and liability of (11)C labeling in the O-methyl position.

Anthranilic acid amides: a novel class of antiangiogenic VEGF receptor kinase inhibitors

Two readily synthesized anthranilamide, VEGF receptor tyrosine kinase inhibitors have been prepared and evaluated as angiogenesis inhibitors. 2-[(4-Pyridyl)methyl]amino-N-[3-(trifluoromethyl)phenyl]benzamide (5) and N-3-isoquinolinyl-2-[(4-pyridinylmethyl)amino]benzamide (7) potently and selectively inhibit recombinant VEGFR-2 and VEGFR-3 kinases. As a consequence of their physicochemical properties, these anthranilamides readily penetrate cells and are absorbed following once daily oral administration to mice. Both 5 and 7 potently inhibit VEGF-induced angiogenesis in an implant model, with ED(50) values of 7 mg/kg. In a mouse orthotopic model of melanoma, 5 and 7 potently inhibited both the growth of the primary tumor as well as the formation of spontaneous peripheral metastases. The anthranilamides 5 and 7 represent a new structural class of VEGFR kinase inhibitors, which possess potent antiangiogenic and antitumor properties.

Melanoma uptake of (99m)Tc complexes containing the N-(2-diethylaminoethyl)benzamide structural element

On the basis of the avid uptake of radioiodinated benzamides by melanoma cells, (99m)Tc complexes containing the structural elements of N-(dialkylaminoalkyl)benzamide pharmacophores have been synthesized and evaluated in vitro and in vivo for melanoma uptake. One of the complexes Tc-12 containing the ligand 4-(S-benzoyl-2-thioacetyl-glycyl-glycylamido)-N-(2-diethylaminoethyl)benzamide (11) displayed the highest melanoma uptake. The 1-h melanoma uptake values and the corresponding blood counts indicate an interdependence of tumor uptake and bioavailability of the (99m)Tc complexes.

Synthesis and insecticidal evaluation of novel N-(S-amino)sulfenylated derivatives of diacylhydrazines

A series of new N-(S-amino)sulfenylated derivatives of diacylhydrazines were synthesized by the reaction of S-aminosulfenyl chlorides with N-tert-butyl-N'-benzoyl-N-substituted benzoylhydrazines in the presence of sodium hydride, and evaluated for moulting hormone mimicking activity. In the course of syntheses, N-N bond cleavage in diacylhydrazines was found and the reaction was studied in some detail. The results of bioassay showed that the title compounds exhibit excellent larvicidal activity. Toxicity assays indicated that these compounds can induce a premature, abnormal and lethal larval mount.