N-acylation reaction offers an opportunity to develop an efficient synthesis of amide group-containing molecules. We found that N-acyl carbazoles showed remarkable selectivity in transamidation. Sterically less hindered primary amines are selectively acylated with N-acyl carbazoles without any additives. Various functional groups such as alcohol, phenol, indole, and aniline moieties are tolerated under mild conditions. The synthetic utility was displayed in one-pot synthesis of an N-acyl polyamine natural product. The terminal amines of spermidine were selectively benzoylated with N-benzoyl carbazole, followed by acetylation reaction accomplished the total synthesis in a highly efficient manner.
Highly selective acylation of polyamines and aminoglycosides by 5-acyl-5-phenyl-1,5-dihydro-4H-pyrazol-4-ones
作者:Kostiantyn O. Marichev、Estevan C. Garcia、Kartick C. Bhowmick、Daniel J. Wherritt、Hadi Arman、Michael P. Doyle
DOI:10.1039/c7sc03184j
日期:——
phenyldiazoacetates, are highly selective acyl transfer reagents for di- and polyamines, as well as aminoalcohols and aminothiols. As reagents with a carbon-based leaving group, they have been applied for benzoyl transfer with a broad selection of substrates containing aliphatic amino in combination with other competing nucleophilic functional groups. The substrate scope and levels of selectivity for direct benzoyl
This invention relates to novel thiohydantoins having the formula: ##SPC1## Wherein R represents lower alkyl or a phenyl or phenyl lower alkyl radical in either of which the phenyl portion may be substituted by halogen, lower alkyl or lower alkoxy; A is oxygen or a direct bond; B represents lower alkylene, R.sup.1 represents hydrogen, or lower alkyl; and R.sup.2 represents lower alkyl or phenyl which may be substituted by halogen, lower alkyl or lower alkoxy, which possess anti-ulcer activity.
A selective stepwise arylation of S−H and N−H bonds in unprotected peptides by air- and moisture- stable PtIV complexes is reported. These compounds showed high reactivity and selectivity toward the N terminal NH2 group over other N−H bonds in complex biologically relevant substrates.
Myxochelin A (1) is an inhibitor of tumor cell invasion produced by the bacterium belonging to the genus Nonomuraea. In order to obtain more potent inhibitors, a series of myxochelin analogues [2 and (S)-3-17] were synthesized through the coupling of lysine or diaminoalkane derivatives and appropriately protected hydroxybenzoate, followed by modification of functional groups and deprotection. These compounds were evaluated for their inhibitory activity against invasion of murine colon 26-L5 carcinoma cells. Among the synthetic analogues tested, compound (S)-6 which possesses carbamoyl group at C-1 was found to be the most potent antiinvasive agent and is considered to be a promising lead molecule for the antimetastasis. Compound (S)-6 was also shown to inhibit gelatinase activities of MMP-2 and MMP-9 and in vivo lung metastasis in mice. (c) 2009 Elsevier Ltd. All rights reserved.