35677-89-5Relevant academic research and scientific papers
β-Lactones as a new class of cysteine proteinase inhibitors: inhibition of hepatitis A virus 3C proteinase by N-Cbz-serine β-Lactone
Lall, Manjinder S.,Karvellas, Constantine,Vederas, John C.
, p. 803 - 806 (1999)
Formula presented N-Benzyloxycarbonyl-L-serine β-lactone (1) is shown to irreversibly inactivate the 3C cysteine proteinase of hepatitis A virus (HAV) with kinact = 0.70 min-1, KI = 1.84 x 10-4 M and kinact/KI = 3800 M-1 min-1 at an enzyme concentration of 0.1 μM. Mass spectrometric and HMQC NMR studies using 13C-labeled 1 show that the active site cysteine (Cys-172) thiol of the HAV 3C proteinase attacks the β-position (i.e. C-4) of the oxetanone ring, thereby leading to ring opening and alkylation of the sulfur. In contrast, the enantiomer of this β-lactone, 2, is a reversible competitive inhibitor (Ki = 1.50 x 10-6 M) at similar enzyme concentrations. The β-lactone motif represents a new class of inhibitors of cysteine proteinases.
Protecting-group-free synthesis of hydroxyesters from amino alcohols
Joseph-Valcin, Eve-Marline,Lebel, Hélène,Reynard, Guillaume
supporting information, p. 10938 - 10941 (2020/10/02)
The synthesis of hydroxyesters from carboxylic acids and unprotected amino alcohols in both continuous flow and batch processes is reported. The formation of a transient diazonium species with a dinitrite reagent is key in this transformation. The reaction conditions are compatible with a variety of functional groups.
Biological evaluation and docking studies of new carbamate, thiocarbamate, and hydrazide analogues of ACYL homoserine lactones as vibrio fischeri-quorum sensing modulators
Zhang, Qiang,Queneau, Yves,Soulère, Laurent
, p. 1 - 12 (2020/05/25)
A series of carbamate, thiocarbamate, and hydrazide analogues of acylhomoserine lactones (AHLs) were synthesized and their ability to modulate Vibrio fischeri-quorum sensing was evaluated. The compounds in the series exhibit variable side chain length and the possible presence of a diversely substituted phenyl substituent. Biological evaluation on the Vibrio fischeri quorum sensing system revealed that the ethyl substituted carbamate (1) display a weak agonistic activity whereas compounds with longer chain length or benzyl substituents display significant antagonistic activity. The most active compounds in the series were the 4-nitrobenzyl carbamate and thiocarbamate 7 and 11 which exhibited an IC50 value of about 20 μM. These activities are in the range of other reported of AHL-structurally related quorum sensing (QS) inhibitors. Docking experiments conducted on the LuxR model showed that, compared to the natural ligand OHHL, the additional heteroatom of the carbamate group induces a new hydrogen bond with Tyr70 leading to a different global hydrogen-bond network. Tyr70 is an important residue in the binding site and is strictly conserved in the LuxR family. For the 4-nitrobenzyl carbamate and thiocarbamate analogues, the docking results highlight an additional hydrogen bond between the nitro group and Lys178. For hydrazide analogues, which are deprived of any activity, docking shows that the orientation of the carbonyl group is opposite as compared with the natural ligand, leading to the absence of a H-bond between the C=O with Tyr62. This suggests that, either this later interaction, or the influence of the C=O orientation on the overall ligand conformation, are essential for the biological activity.
Efficient and Selective Cu/Nitroxyl-Catalyzed Methods for Aerobic Oxidative Lactonization of Diols
Xie, Xiaomin,Stahl, Shannon S.
, p. 3767 - 3770 (2015/04/14)
Cu/nitroxyl catalysts have been identified that promote highly efficient and selective aerobic oxidative lactonization of diols under mild reaction conditions using ambient air as the oxidant. The chemo- and regioselectivity of the reaction may be tuned by changing the identity of the nitroxyl cocatalyst. A Cu/ABNO catalyst system (ABNO = 9-azabicyclo[3.3.1]nonan-N-oxyl) shows excellent reactivity with symmetrical diols and hindered unsymmetrical diols, whereas a Cu/TEMPO catalyst system (TEMPO = 2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl) displays excellent chemo- and regioselectivity for the oxidation of less hindered unsymmetrical diols. These catalyst systems are compatible with all classes of alcohols (benzylic, allylic, aliphatic), mediate efficient lactonization of 1,4-, 1,5-, and some 1,6-diols, and tolerate diverse functional groups, including alkenes, heterocycles, and other heteroatom-containing groups.
Concise Synthesis of Enantiomerically Pure (1′S,2′R)-and (1′R,2′S)-2S-Amino-3-(2′-aminomethyl-cyclopropyl)propionic Acid: Two E-Diastereoisomers of 4,5-Methano-l-lysine
Altamore, Timothy M.,Nguyen, Oanh T. K.,Churches, Quentin I.,Cavanagh, Kate,Nguyen, Xuan T. T.,Duggan, Sandhya A. M.,Krippner, Guy Y.,Duggan, Peter J.
, p. 1105 - 1111 (2013/09/24)
A concise synthesis of both E-isomers of 2S-amino-3-(2′-aminomethyl- cyclopropyl)propionic acid, new methano-l-lysines, is described. The synthetic route includes nine steps from l-methionine, with a key step involving the cyclopropanation of an intermediate E-allylic alcohol. The resultant hydroxymethylcyclopropanes were readily separated and converted into the title α-amino acids. The stereochemistry around the cyclopropane rings was deduced by conducting the cyclopropanation in the presence of N,N,N′,N′-tetramethyl-d-tartaric acid diamide butylboronate, a chiral controller which is known to favour the production of S-hydroxymethyl cyclopropanes from allylic alcohols.
A microwave-assisted synthesis of (S)-N-protected homoserine γ-lactones from l-aspartic acid
Singh, Suneel P.,Michaelides, Alex,Merrill, A. Rod,Schwan, Adrian L.
experimental part, p. 6825 - 6831 (2011/10/08)
A three-pot preparation of (S)-N-protected homoserine γ-lactones is presented. Conversion of N-protected l-aspartic acid to an oxazolidinone is followed by selective reduction/acid-catalyzed cyclization to deliver the lactones. Microwave irradiation proved valuable for improving the latter reaction steps in some cases.
ETHER DERIVATIVE
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Page/Page column 40, (2008/06/13)
The present invention relates to an ether derivative represented by the formula (I), a pharmaceutically acceptable salt thereof, a hydrate thereof or a solvate thereof wherein each symbol is as defined in the description, and an ether derivative represented by the formula (III), a pharmaceutically acceptable salt thereof, a hydrate thereof or a solvate thereof wherein each symbol is as defined in the description; a pharmaceutical composition containing the ether derivative; and a package containing the pharmaceutical composition and a description of use thereof. A pharmaceutical composition of the present invention, which contains this compound of the present invention has a superior anti-inflammatory and analgesic activity and is useful as various pharmaceutical agents such as an anti-inflammatory agent, an analgesic, a therapeutic agent for inflammatory bowel disease, a therapeutic agent for pollakiuria and/or incontinentia, a therapeutic agent for asthma and the like.
Enantioselective Synthesis of Non-Natural Aromatic α-Amino Acids
Krebs, Andreas,Ludwig, Verena,Pfizer, Jose,Duerner, Gerd,Goebel, Michael W.
, p. 544 - 553 (2007/10/03)
We present two complementary methods for the stereoselective synthesis of non-natural α-amino acids with aromatic or heteroaromatic side chains. One approach is based on the chemical transformation of methionine, whereas the other applies the stereoselective Myers alkylation of glycine. The resulting product types differ in the linker length between glycine and the aromatic substituent. Since methionine and pseudoephedrine are available in both absolute configurations, R- or S-configured enantiopure amino acids with either C2 or C3 linkers can be obtained on gram scales. In each case the key step of the synthesis is hydroboration of the unsaturated building blocks 9 and 17, followed by palladium-catalyzed Suzuki cross-coupling with aryl halides. Attention must in certain cases be paid to the stereochemical integrity when basic Suzuki conditions are applied. Our initial difficulties are reported as well as the final "racemization-proof" procedures. The protecting groups chosen for the α-amino acids should be compatible with solid-phase peptide synthesis. This was confirmed by the successful synthesis of a series of tripeptides.
An efficient procedure for the preparation of 4-substituted 5-aminoimidazoles
McLaughlin, Mark,Mohareb, Rafat M.,Rapoport, Henry
, p. 50 - 54 (2007/10/03)
The preparation of O-methylimidates from α-aminonitriles and their subsequent co-cyclization with primary amines to afford 4-substituted 5-aminoimidazoles was studied. It was found that the mildly acidic pyridinium p-toluenesulfonate efficiently catalyzed each stage of the reaction sequence: (a) the formation of the O-methylimidates, (b) their co-cyclization with a variety of primary amines, and (c) certain derivatizations of the resultant heterocycles. The developed reaction conditions tolerate a wide variety of α-aminonitriles and primary amine co-reactants. Thus, it is possible to easily prepare a diverse array of substituted heterocyclic compounds in good yield. The requisite α-aminonitriles were synthesized either from amino acids or by phase-transfer alkylation of a glycine anion equivalent. The unstable free 5-aminoimidazoles were normally protected in situ to provide derivatives (methyl imidates or N,N-dimethylamidines) that were amenable to characterization.
Synthesis and in vitro enzyme activity of aza, oxa and thia derivatives of bacterial cell wall biosynthesis intermediates
Cox,Wang
, p. 2022 - 2034 (2007/10/03)
Mechanism based inhibitors of diaminopimelate aminotransferase (DAP-AT) were designed using knowledge of its substrate specificity and mechanism. Synthesis of thiolester and amide substrate analogues was achieved prior to in vitro inhibition studies, but ester analogues proved too unstable to isolate. Thia substrate analogues showed no inhibitory properties, but the aza substrate analogue 12a showed reversible inhibition vs. DAP-AT and time dependent inhibition in the absence of the natural substrate 4. Substrate analogue 12a is thefirst example of an amide inhibitor of PLP dependent enzymes. Antibiotic properties of 12a were also briefly assessed.
