Two proteolytic activities that convert big ET to ET at neutral pH were identified in solubilized membranes prepared from rat lung. The endothelin-converting activities were partially purified by using A80227 (2S,3R,4S)-2-{[N-acetylcyclohexylalanyl- isoleucyl]amino}-1-(2-naphthyl)-3,4-dihydroxy-...

IntroductionStent thrombosis (ST) is a rare but catastrophic complication of percutaneous coronary intervention, leading to poor prognosis. Endothelin-1 (ET-1) plays an important role in endothelial dysfunction and thrombogenesis. However, the impact of big ET-1 level on ST in patients with coro...

AimWe examined whether there is a differential effect of endothelin-A antagonism on coronary artery compliance in type 2 diabetes mellitus compared to non-diabetic patients.

SummaryBackground and objectivesInsulin modulates key regulators of vascular tone, including endothelin-1 (ET-1), hence insulin resistance (IR) and/or hyperinsulinemia may contribute to the pathogenesis of hypertension and cardiovascular disease (CVD). Imbalance in ET-1/nitric oxide may link IR ...

BackgroundCardiac remodeling is one of major pathological process in hypertrophic cardiomyopathy (HCM). Endothelin-1 has been linked to cardiac remodeling. Big endothelin-1 is the precursor of endothelin-1.

The biosynthetic pathway of endothelin (ET)-2 was analyzed in cultured ACHN cells. In the supernatant, we detected three ET-2-related peptides, ET-2, big ET-2(1–38) and big ET-2(22–28). Phosphoramidon decreased the amount of ET-2 and increased that of big ET-2(13̄8)dose-dependently. The...

Purified monkey chymase cleaved the Tyr31–Gly32 bond of big-endothelin-1 and big-endothelin-2 to yield endothelin-1-(1–31) and endothelin-2-(1–31), respectively. In the isolated monkey trachea, endothelin-1-(1–31) and endothelin-2-(1–31), as well as big-endothelin-1 and big-endothelin-2, in...

Radiolabeled amino acids represent a promising class of tumor imaging agents, and the determination of the optimal characteristics of these tracers remains an area of active investigation. A new 18F-labeled branched amino acid, 2-amino-4-[18F]fluoro-2-methylbutanoic acid (FAMB), has been prepare...

This review discusses recent publications on the separation and analysis of natural and unnatural amino acid enantiomers by liquid chromatography. Focus is placed on methodological aspects relating chiral stationary phases and chiral columns which can cope with the challenge. Conceptually, amino...

A series of N-(3-(4-hydroxyphenyl)-propenoyl)-amino acid tryptamides was based on a previously reported new SIRT2 inhibitor from our group, and it was designed to study if the molecular size of the compound could be reduced. The most potent compounds, N-(3-(4-hydroxyphenyl)-propenoyl)-2-aminoiso...

Two diastereomeric six-membered ring α,α-disubstituted α-amino acids (1R,3R)- and (1S,3R)-1-amino-3-methylcyclohexanecarboxylic acids (Ac6c3M); side-chain restricted leucine analogs, were stereoselectively synthesized from (3R)-3-methylcyclohexanone by a Bucherer–Bergs or Strecker reaction. ...

The protected (2S,4R)-2-amino-4-methyldecanoic acid, a proposed component of culicinins has been synthesized over 10 steps and in total 28% yields using Wittig reaction and Schöllkopf amino acid synthesis as key steps.

Chiral cyclic α,α-disubstituted α-amino acids with four chiral centers at their acetal moieties were synthesized. An X-ray crystallographic analysis of homo-chiral tripeptide with (2R,3R)-butane-2,3-diol acetal moieties revealed that the tripeptide formed both (P) and (M) helical structures, ...

Replacing a hypothetical i + 3 → i peptide H-bond in a disordered pentapeptide, that lacks any helicogenic Cα-tetrasubstituted residues, with a propyl linker and carbamylating the N-terminal nitrogen constrains it in the elusive 310-helical structure with high helicity and stability under vary...

Novel α-amino squaric acid analogs were synthesized by initial addition reaction of a dianion enolate generated from N-Boc amino acid tert-butyl ester to squaric acid diisopropyl ester, and subsequent decarboxylation of the resulting carboxylic acid moiety.

A kinetic study of the hydrogen atom transfer (HAT) reaction from a series of N-Boc- or N-Acetyl-protected amino acids to the phthalimide N-oxyl radical (PINO) was carried out to obtain information about reactivity and selectivity patterns. With amino acids containing aliphatic side chains, the ...

In this paper we present a pyridine synthesis, starting from N-protected amino acids. Amino acids are firstly converted to an ynone system, which is later converted to an enaminone system. Following a formal [2 + 2] cycloaddition of electron poor acetylenes and subsequent ring closure the final ...

We report a room temperature and ligand-free copper-catalyzed coupling of α-amino acid with N-Boc-2-iodoanilines. The initially obtained N-arylated α-amino acids could be subsequently transformed into enantiomerically pure 3-aryl or 3-alkyl-substituted dihydroquinoxalinones via acid-mediated B...

(S)-2-Boc-Amino-8-(R)-(tert-butyldimethylsilanyloxy)decanoic acid, the Boc-protected precursor of an unusual amino acid residue for the synthesis of microsporin B, was synthesized. The key steps include a Suzuki coupling followed by asymmetric homogeneous hydrogenation.

Camptothecin (CPT), a quinolone alkaloid extracted from Camptotheca acuminata Decne, exhibits potential insecticidal activities against various insect species. Our previous studies have showed that CPT induced apoptosis in Spodoptera exigua Hübner cell line and inhibited the relaxation activity...