72155-46-5Relevant academic research and scientific papers
AHPPA derivative and its preparation method
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Paragraph 0010; 0016; 0017; 0017; 0018, (2017/04/18)
The invention discloses AHPPA derivatives and a preparation method thereof. The preparation method utilizes a diethylzinc-stannic chloride mixture with a mole ratio of 1: 2-4 as a catalyst, improves a reaction temperature and a yield and is suitable for industrial production.
Helices with additional H-bonds: crystallographic conformations of α,γ-hybrid peptides helices composed of β-hydroxy γ-amino acids (statines)
Malik, Ankita,Kumar, Mothukuri Ganesh,Bandyopadhyay, Anupam,Gopi, Hosahudya N.
, (2017/02/05)
β-Hydroxy-γ-amino acids (Statines) are a class of naturally occurring non-ribosomal amino acids frequently found in many peptide natural products. Peptidomimetics constituted with statines have been used as inhibitors for various aspartic acid proteases. In contrast to the synthetic γ-amino acids, very little is known about the folding behavior of these naturally occurring β-hydroxy γ-amino acids. To understand the folding behavior of statines, three α,γ-hybrid peptides P1 (Ac-Aib-γPhe-Aib-(R, S)Phesta-Aib-γPhe-Aib-CONH2), P2 (Ac-Aib-γPhe-Aib-(S, S)Phesta-Aib-γPhe-Aib-CONH2), and P3 (Ac-Aib-γPhe-Aib-(S, S)Phesta-Aib-(S, S)Phesta-Aib-CONH2) were synthesized on solid phase and their helical conformations in single crystals were studied. Results suggest that both syn and anti diastereoisomers of statines can be accommodated into the helix without deviating overall helical conformation of α,γ-hybrid peptides. In comparison with syn diastereoisomer, the anti diastereoisomer was found to be directly involved in the intramolecular H-bonding with the backbone carbonyl groups (i to i + 3) similar to the backbone amide NHs in the helix.
Novel renin inhibitors containing derivatives of N-alkylleucyl-β-hydroxy-γ-amino acids
Winiecka, Iwona,Jaworski, Pawe?,Mazurek, Aleksander Pawe?,Marsza?ek, Dorota,Goldnik, Anna,Sokulski, Daniel
, p. 106 - 115 (2016/02/09)
In search for new drugs lowering arterial blood pressure, which could be applied in anti-hypertensive therapy, research concerning agents blocking of renin-angiotensin-aldosteron system has been conducted. Despite many years of research conducted at many research centers around the world, aliskiren is the only one renin inhibitor, which is used up to now. Four novel potential renin inhibitors, having structure based on the peptide fragment 8-13 of human angiotensinogen, a natural substrate for renin, were designed and synthesized. All these inhibitors contain unnatural moieties that are derivatives of N-methylleucyl-β-hydroxy-γ-amino acids at the P2-P1' position: 4-[N-(N-methylleucyl)-amino]-3-hydroxy-7-(3-nitroguanidino)-heptanoic acid (AHGHA), 4-[N-(N-methylleucyl)-amino]-3-hydroxy-5-phenyl-pentanoic acid (AHPPA) or 4-[N-(N-methylleucyl)-amino]-8-benzyloxycarbonylamino-3-hydroxyoctanoic acid (AAHOA). The previously listed synthetic β-hydroxy-γ-amino acids constitute pseudodipeptidic units that correspond to the P1-P1' position of the inhibitor molecule. An unnatural amino acid, 4-methoxyphenylalanin (Phe(4-OMe)), was introduced at the P3 position of the obtained compounds. Three of these compounds contain isoamylamide of 6-aminohexanoic acid (ε-Ahx-Iaa) at the P2'-P3' position. The proposed modifications of the selected human angiotensinogen fragment are intended to increase bioactivity, bioavailability, and stability of the inhibitor molecule in body fluids and tissues. The inhibitor Boc-Phe(4-OMe)-MeLeu-AHGHA-OEt was obtained in the form of an ethyl ester. The hydrophobicity coefficient, expressed as log P varied between 3.95 and 8.17. In vitro renin inhibitory activity of all obtained compounds was contained within the range 10-6-10-9 M. The compound Boc-Phe(4-OMe)-MeLeu-AHPPA-Ahx-Iaa proved to be the most active (IC50 = 1.05 × 10-9 M). The compounds Boc-Phe(4-OMe)-MeLeu-AHGHA-Ahx-Iaa and Boc-Phe(4-OMe)-MeLeu-AHPPA-Ahx-Iaa are resistant to chymotrypsin.
Exploring β-hydroxy γ-amino acids (statines) in the design of hybrid peptide foldamers
Bandyopadhyay, Anupam,Malik, Ankita,Kumar, Mothukuri Ganesh,Gopi, Hosahudya N.
supporting information, p. 294 - 297 (2014/01/23)
The synthesis and characterization of syn and anti β-hydroxy γ-amino acid (statine) diastereoisomers, their utilization in the design of hybrid peptide foldamers, and their single crystal conformations are studied.
Stereoselective synthesis of four possible isomers of streptopyrrolidine
Mohapatra, Debendra K.,Thirupathi, Barla,Das, Pragna P.,Yadav, Jhillu S.
experimental part, p. 34 - 39 (2011/03/22)
The synthesis of (4R,5R)-streptopyrrolidine (1), (4S,5R)-streptopyrrolidine (2) (4R, 5S)-streptopyrrolidine (3) and (4S,5S)-strepto- pyrrolidine (4) have been achieved in a concise and highly efficient manner via a highly stereoselective aldol type reacti
Mechanism-based inhibitors of the aspartyl protease plasmepsin II as potential antimalarial agents
Gupta, Deepak,Yedidi, Ravikiran S.,Varghese, Sheeba,Kovari, Ladislau C.,Woster, Patrick M.
experimental part, p. 4234 - 4247 (2010/08/22)
Four aspartyl proteases known as plasmepsins are involved in the degradation of hemoglobin by Plasmodium falciparum, which causes a large percentage of malaria deaths. The enzyme plasmepsin II (Plm-II) is the most extensively studied of these aspartyl proteases and catalyzes the initial step in the breakdown of hemoglobin by the parasite. Several groups have reported the design, synthesis, and evaluation of reversible peptidomimetic inhibitors of Plm II as potential antimalarial agents. We now report four peptidomimetic analogues, compounds 6-9, which are rationally designed to act as mechanism-based inhibitors of Plm II. Three of these analogues produce potent irreversible inactivation of the enzyme with IC50 values in the low nanomolar range. Of these three compounds, two retain the low micromolar IC 50 values of the parent compound in Plasmodium falciparum (clone 3D7) infected erythrocytes. These analogues are the first examples of fully characterized mechanism-based inactivators for an aspartyl protease and show promise as novel antimalarial agents.
Solid-Phase Synthesis of β-Lactams via the Miller Hydroxamate Approach
Meloni, Marco Massimiliano,Taddei, Maurizio
, p. 337 - 340 (2007/10/03)
(Matrix Presented) β-Lactams were prepared on solid phase starting from serine, threonine, or other β-hydroxyacids derived from naturally occurring amino acids and a resin bound hydroxylamine. The ring closure was carried out under Mitsunobu conditions. The amino group present on the β-lactam was used to assemble a short peptide. After a reductive cleavage with Sml2, β-lactam-containing peptides were obtained.
Total synthesis and conformational studies of hapalosin, N-desmethylhapalosin and 8-Deoxyhapalosin
Wagner, Bjoern,Gonzalez, Gabriel Islas,Tran Hun Dau, Marie Elise,Zhu, Jieping
, p. 737 - 747 (2007/10/03)
Hapalosin (2), a 12-membered cyclic depsipeptide possessing MDR-reversing activity, and analogues (3) and (4) have been synthesized using macrolactamization as an important ring-forming step. Three building blocks: (2S, 3R)-3-(tert-butyldimethylsilyloxy)-2-methyl-decanoic acid (13), benzyl (S)-2-hydroxy-3-methylbutanate (14), and (4S,3R)-4-(benzyloxycarbonyl-methylamino)-3-methoxymethoxy-5-phenyl-pentanoic acid (28) were prepared from Evans's chiral imide (9), l-valine, and l-N-Boc phenylalanine (17), respectively, and were assembled together by applying twice Yamaguchi's coupling methodology. A new and efficient selective N-methylation of γ-hydroxy-β-amino ester taking advantage of the vicinal amino alcohol function was uncovered in the course of this study. Thus, treatment of compound 19 with HCHO in the presence of catalytic amount of pTsOH followed by reduction (NaBH3CN, TFA, CH2Cl2) of the so-formed oxazolidine 24 gave the N-methylated product 25. Furthermore, a dual role of oxazolidine as protecting group of vicinal amino alcohol and latent N-methyl function was established which allowed synthesizing both hapalosin (2) and N-desmethylhapalosin (3) from the same linear precursor 32 in a step-efficient and atom economic way. In contrast to hapalosin (2) and N-desmethyl analogue (3), the amide bond of 8-deoxy hapalosin (4) exists at room temperature (CDCl3) exclusively in s-cis conformation as evidenced by NOE studies. This observation has been explained on the basis of computational studies. No significant MDR reversing activity of 8-deoxy hapalosin (4) was observed in K562 R and S/Adriblastine against human erythroleucemic cell lines indicating thus the important contribution of hydroxy group to the bioactivity of hapalosin. Copyright (C) 1999 Elsevier Science Ltd.
A Novel, Facile and Diastereoselective Synthesis of (3S,4S) and (3R,4S)-N-Me-AHPPA
Reddy, G. Vidyasagar,Rao, G. Venkat,Iyengar, D. S.
, p. 703 - 704 (2007/10/03)
Diastereoselective syntheses of (3S,4S) and (3R,4S)-N-methyl-AHPPA are achieved via a novel Wittig reaction of an oxazolidinone followed by reduction.
