53370-84-6Relevant articles and documents
THIOSEMICARBAZATES AND USES THEREOF
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Paragraph 00147; 00210, (2020/11/23)
Thioesters, thiocarbamates, thiocarbazates, semithiocarbazates, peptides, aza-amino acid conjugates, and azapeptides; and a chemoselective and site-specific functionalization protocol of protected thiocarbazates and semithiocarbazates are described. The protocol features the use of Mitsunobu reaction to alkylate specifically the nitrogen atom close to the acylthiol moiety with alcohols to produce protected mono-substituted thiocarbazates that can be stored for months, activated under mild conditions at low temperature using halonium reagents and integrated orthogonally to make substituted semicarbazides that can be used, e.g., as synthons in synthesis of aza-amino acid conjugates, azapeptides and other peptidomimetics. Methods for preparing and using ureases, carbazides, semicarbazides, beta-peptides, azapeptides, and other peptidomimetics and azapeptide conjugates, and uses of ureases, carbazides, semicarbazides, beta-peptides, azapeptides in drug discovery, diagnosis, inhibition, prevention and treatment of diseases are also described.
Synthesis of Macrocycles Derived from Substituted Triazines
Yepremyan, Akop,Mehmood, Arshad,Asgari, Parham,Janesko, Benjamin G.,Simanek, Eric E.
, p. 241 - 246 (2018/12/11)
A triazine ring derivatized with morpholine, an N-alkyl-N′-BOC-hydrazine (alkyl=isopropyl or benzyl) and the diethylacetal of glycinylpropionaldehyde undergoes spontaneous dimerization in good yields upon acid-catalyzed deprotection. The resulting 24-member macrocycles can be characterized by NMR spectroscopy, mass spectrometry, and single crystal X-ray diffraction. In the solid state, both homodimers adopt a taco-like conformation. Although each shows π–π stacking between the triazine rings, different patterns of hydrogen bonds emerge. The crystal structure of the isopropyl dimer shows that it includes two molecules of trifluoracetic acid per macrocycle. The trifluoroacetate anion charge balances the protonated triazines, which engage in bifurcated hydrogen bonds with the carbonyl acceptor of the distant glycine. This carbonyl also forms a hydrogen bond with the NH of the proximate glycine. The crystal structure of the benzyl derivative does not include trifluoracetic acid. Instead, two hydrogen bonds form, each between a glycine NH and the lone pair of the C=N nitrogen of the hydrazine group. In the solid state, both molecules present the alkyl side chains and morpholine groups in close proximity. A heterodimer is accessible in approximately statistical yields—along with both homodimers—by mixing the two protected monomers prior to subjecting them to deprotection.
Towards a general synthesis of di-aza-amino acids containing peptides
Bizet, Faustine,Tonali, Nicolo,Soulier, Jean-Louis,Oliva, Agostino,Kaffy, Julia,Crousse, Benoit,Ongeri, Sandrine
, p. 17062 - 17072 (2018/10/23)
While the incorporation of one aza-amino acid in peptides has been proved to be beneficial for inducing a structure constraint, increasing the resistance towards proteolysis and improving the biological activity, only very rare examples of the incorporation of two or more consecutive aza-amino acids have been reported. In this work, we demonstrate that this fact is probably due to the unsuspected difficulty in synthesizing such peptide analogues, as illustrated by the synthesis of tripeptide derivatives containing two consecutive aza-amino acids. Herein, we report some general guidelines regarding the activation and the coupling of alkyl-hydrazides either mutually or with a natural amino acid, taking into account their nucleophilicity and the nature of their side chains.