The flavonoid genistein and the benzo[c]quinolizinium MPB-07 have been shown to activate the cystic fibrosis transmembrane conductance regulator (CFTR), the protein that is defective in cystic fibrosis. Lead-based combinatorial and parallel synthesis yielded 223 flavonoid, quinolizinium, and related heterocyclic compounds. The compounds were screened for their ability to activate CFTR at 50 μmconcentration by measurement of the kinetics of iodide influx in Fisher rat thyroid cells expressing wild-type or G551D CFTR together with the green fluorescent protein-based halide indicator YFP-H148Q. Duplicate screenings revealed that 204 compounds did not significantly affect CFTR function. Compounds of the 7,8-benzoflavone class, which are structurally intermediate between flavones and benzo[c]quinoliziniums, were effective CFTR activators with the most potent being 2-(4-pyridinium)benzo[h]4H-chromen-4-one bisulfate (UCcf-029). Compounds of the novel structural class of fused pyrazolo heterocycles were also strong CFTR activators with the most potent being 3-(3-butynyl)-5-methoxy-1-phenylpyrazole-4-carbaldehyde (UCcf-180). A CFTR inhibitor was also identified. The active compounds did not induce iodide influx in null cells deficient in CFTR. Short-circuit current measurements showed that the CFTR activators identified by screening induced strong anion currents in the transfected cell monolayers grown on porous supports. Compared with genistein, the most active compounds had up to 10 times greater potency in activating wild-type and/or G551D-CFTR. The activators had low cellular toxicity and did not elevate cellular cAMP concentration or inhibit phosphatase activity, suggesting that CFTR activation may involve a direct interaction. These results establish an efficient screening procedure to identify CFTR activators and inhibitors and have identified 7,8-benzoflavones and pyrazolo derivatives as novel classes of CFTR activators.

Optically active derivatives of vesamicol are prepared using solid-phase chemistry. Zincke coupling of resin-bound amino ethers (trityl linker) with 2,4-dinitrophenyl pyridinium salts delivers Zincke products which can be (1) liberated from the resin (TFA) or (2) reduced (NaBH4) to tetrahydropyridine derivatives and liberated. Subsequent reduction (H2/Pd) gives piperidines.

Mechanistic aspects of the solid-phase Zincke reaction have been investigated using Wang resins; a proton transfer mechanism is proposed which obviates the need for covalent bond site-site interactions.

A study of structural modifications of MPB-07 was undertaken as part of a synthetic program aimed at discovering small molecules with CFTR activation potential. Solid-phase synthesis techniques were used to prepare derivatives of MPB-07 employing the Zincke reaction for the construction of aromatic, quaternary ammonium salts such as those found in 2 or 3. In this transformation, primary amines react with highly electrophilic N-2,4-dinitrophenylpyridinium (DNP) salt 4 to afford pyridinium salt 8 with release of 2,4-dinitroaniline 6. Thus, the reaction of 1-(2,4-dinitrophenyl)pyridinium salts with various polymer-bound amino ethers, followed by cleavage from the resin, delivers the desired salts in good yield and high purity.

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Appropriate structural modification of the difluoromethylene ketone derivatives at both P3 and P' positions led us to the discovery of peptidyl human heart chymase inhibitor 12h which shows potent activity with Ki = 6 nM and high selectivity against closely related serine protease bovine alpha-chymotrypsin (chymotrypsin Ki = > 100 microM). Using the compound 12b, a docking study with human heart chymase was carried out to presume probable interactions.

Peptidyl difluoromethylene ketone derivatives were designed to take advantage of probable additional interactions with the S' subsite of human heart chymase. They showed potent inhibitory activities against human heart chymase and were more efficient than bovine chymotrypsin.

The following alterations should be made to the text to improve the clarity of the paper: Page 919. The authors and affiliations should read as follows: Masahiro Eda’, Atsuyuki Ashimori’,‘, Fumihiko Akahoshi’, Takuya Yoshimura’, Yoshihisa Inoue’, Chikara Fukaya’, Masahide Nakajima’, Hajime Fukuyama’, Teruaki Imada’, Shinji Taka?, Naotaka Shiota*, Mizuo Miyazaki*, Norifumi Nakamura’

La presente invention concerne des composes heterocycliques representes par la formule generale (I) ou certains de leurs sels acceptables en pharmacologie. L'invention concerne egalement une composition medicinale comprenant ces composes. La signification des symboles de la formule generale est donnee dans la description de l'invention. Faisant preuve d'une bonne activite d'inhibition des chymases chez les mammiferes, y compris chez l'homme, et pouvant s'administrer par voie orale ou parenterale, ces composes heterocycliques et leurs sels acceptables en pharmacologie presentent un interet comme inhibiteurs des chymases et conviennent particulierement au traitement preventif et curatif de diverses affections imputables aux chymases, et notamment de celles qui sont imputables a l'angiotensine II.

A series of amino acid conjugates of N-(6-amino-3-pyridyl)-N'-[exo-bicyclo[2.2.1]hept-2-yl]-N''- cyanoguanidine (4) were prepared and evaluated as antihypertensive agents. The parent compound 4 showed potent potassium channel-opening and antihypertensive activities, but with undesirable changes of the urinary balance of electrolytes. However, alanine and histidine congeners (9,19) reduced this undesirable side effect of 4 through improved pharmacokinetics without loss of antihypertensive activity. They also provided additional information on the structural requirements for pinacidil-type potassium channel openers.

1. The effects of AL0671, a novel potassium channel opener, on protein glycation and low-density lipoprotein (LDL) oxidation were tested. 2. AL0671 dose-dependently inhibited both fluorescence development of bovine serum albumin and cross-linking of lysozyme. These inhibitory effects for glycation were no less potent than aminoguanidine. 3. AL0671 dose-dependently inhibited both increase in negative charge and apo B-100 fragmentation during incubation of LDL with Cu2+. In addition, AL0671 significantly decreased the LDL degradation in rat peritoneal macrophages. 4. Neither pinacidil nor levcromakalim inhibited protein glycation and LDL oxidation. 5. Antioxidant properties of AL0671 might be due to its potent electron-donating ability, and this agent is expected to be useful for hypertensive diabetes.

The crystal structure of [(1S * ,2R * ,4R * )-bicyclo[2.2.1]hept-2-yl]-2-cyanoguanidine (AL0670) acetonitrile solvate, C 14 H 18 N 6 .CH 3 CN, has been determined by X-ray diffraction.