41721-01-1Relevant articles and documents
Orthogonal Catalysis for an Enantioselective Domino Inverse-Electron Demand Diels?Alder/Substitution Reaction
Beeck, Sebastian,Ahles, Sebastian,Wegner, Hermann A.
, (2021/12/09)
An enantioselective domino process for the synthesis of substituted 1,2-dihydronaphthalenes has been developed by the combination of chiral amines and a bidentate Lewis acid in an orthogonal catalysis. This new method is based on an inverse electron-demand Diels?Alder and a subsequent group exchange reaction. An enamine is generated in situ from an aldehyde and a chiral secondary amine catalyst that reacts with phthalazine, activated by the coordination to a bidentate Lewis acid catalyst. The absolute configuration of the product is controlled by chiral information provided by the amine. The formed ortho-quinodimethane intermediate is then transformed via a group exchange reaction with thiols. The new method shows a broad scope and tolerates a wide range of functional groups with enantiomeric ratios up to 91 : 9. All-in-all, this enantioselective synthesis tool provides an easy access to complex 1,2-dihydronaphthalenes starting from readily available phthalazine, aldehydes and thiols in a combinatorial way.
Targeting the Src Homology 2 (SH2) Domain of Signal Transducer and Activator of Transcription 6 (STAT6) with Cell-Permeable, Phosphatase-Stable Phosphopeptide Mimics Potently Inhibits Tyr641 Phosphorylation and Transcriptional Activity
Mandal, Pijus K.,Morlacchi, Pietro,Knight, J. Morgan,Link, Todd M.,Lee, Gilbert R.,Nurieva, Roza,Singh, Divyendu,Dhanik, Ankur,Kavraki, Lydia,Corry, David B.,Ladbury, John E.,McMurray, John S.
, p. 8970 - 8984 (2015/12/09)
Signal transducer and activator of transcription 6 (STAT6) transmits signals from cytokines IL-4 and IL-13 and is activated in allergic airway disease. We are developing phosphopeptide mimetics targeting the SH2 domain of STAT6 to block recruitment to phosphotyrosine residues on IL-4 or IL-13 receptors and subsequent Tyr641 phosphorylation to inhibit the expression of genes contributing to asthma. Structure-affinity relationship studies showed that phosphopeptides based on Tyr631 from IL-4Rα bind with weak affinity to STAT6, whereas replacing the pY+3 residue with simple aryl and alkyl amides resulted in affinities in the mid to low nM range. A set of phosphatase-stable, cell-permeable prodrug analogues inhibited cytokine-stimulated STAT6 phosphorylation in both Beas-2B human airway cells and primary mouse T-lymphocytes at concentrations as low as 100 nM. IL-13-stimulated expression of CCL26 (eotaxin-3) was inhibited in a dose-dependent manner, demonstrating that targeting the SH2 domain blocks both phosphorylation and transcriptional activity of STAT6.
New benzylureas as a novel series of potent, nonpeptidic vasopressin V2 receptor agonists
Yea, Christopher M.,Allan, Christine E.,Ashworth, Doreen M.,Barnett, James,Baxter, Andy J.,Broadbridge, Janice D.,Franklin, Richard J.,Hampton, Sally L.,Hudson, Peter,Horton, John A.,Jenkins, Paul D.,Penson, Andy M.,Pitt, Gary R. W.,Rivière, Pierre,Robson, Peter A.,Rooker, David P.,Semple, Graeme,Sheppard, Andy,Haigh, Robert M.,Roe, Michael B.
body text, p. 8124 - 8134 (2009/11/30)
Vasopressin (AVP) is a hormone that stimulates an increase in water permeability through activation of V2 receptors in the kidney. The analogue of AVP, desmopressin, has proven an effective drug for diseases where a reduction of urine output is desired. However, its peptidic nature limits its bioavailability. We report herein the discovery of potent, nonpeptidic, benzylurea derived agonists of the vasopressin V2 receptor. We describe substitutions on the benzyl group to give improvements in potency and subsequent modifications to the urea end group to provide improvements in solubility and increased oral efficacy in a rat model of diuresis. The lead compound 20e (VA106483) is reported for the first time and has been selected for clinical development.
Aminocarbonyloxymethyl ester prodrugs of flufenamic acid and diclofenac: Suppressing the rearrangement pathway in aqueous media
Ribeiro, Lina,Silva, Nuno,Iley, Jim,Rautio, Jarkko,Jaervinen, Tomi,Mota-Filipe, Helder,Moreira, Rui,Mendes, Eduarda
, p. 32 - 40 (2007/10/03)
Aminocarbonyloxymethyl ester prodrugs are known to undergo rearrangement in aqueous solutions to form the corresponding N-acylamine side product via an O → N intramolecular acyl transfer from the carbamate conjugate base. Novel aminocarbonyloxymethyl esters of diclofenac and flufenamic acid containing amino acid amide carriers were synthesized and evaluated as potential prodrugs displaying less ability to undergo rearrangement. These compounds were prepared in reasonable yield by a four-step synthetic method that uses the appropriate N-Boc-protected amino acid N-hydroxysuccinimide ester and secondary amine and chloromethyl chloroformate as key reactants. Their reactivity in pH 7.4 buffer and 80% human plasma at 37°C was assessed by RP-HPLC. The aminocarbonyloxymethyl esters containing a secondary carbamate group derived from amino acids such as glycine or phenylalanine were hydrolyzed quantitatively to the parent drug both in non-enzymatic and enzymatic conditions, with no rearrangement product being detected. The oral bioavailability in rats was determined for selected diclofenac derivatives. These derivatives displayed a bioavailability of 25 to 68% relative to that of diclofenac, probably due to their poor aqueous solubility and lipophilicity. These results suggest that further optimization of aminocarbonyloxymethyl esters as potential prodrugs for non-steroidal anti-inflammatory drugs require the use of amino acid carriers with ionizable groups to improve aqueous solubility.
Amino acids and peptides. XVI. Synthesis of N-terminal tetrapeptide analogs of fibrin α-chain and their inhibitory effects on fibrinogen/thrombin clotting
Kawasaki,Hirase,Miyano,Tsuji,Iwamoto
, p. 3253 - 3260 (2007/10/02)
N-Terminal tetrapeptide analogs of fibrin α-chain were synthesized by the solution method using a new active ester, the ester of the oxime of p-nitroacetophenone, and by the solid-phase method. Their inhibitory effects on fibrinogen/thrombin clotting were examined. Of the synthetic peptides, amide analogs of Gly-Pro-Arg-Pro exhibited a more potent inhibitory effect.
