Phosphinyl dipeptide isosteres (PDIs) are important compounds for the development of potent and selective inhibitors of various aspartic proteases and Zn metalloproteases. The stereochemistry of PDIs affects their biological activity. PDIs were prepared successfully using the concept of asymmetric induction from the chiral phosphorus atom of the phosphinate moiety to the neighboring carbon atom...

A series of 2,5,7-trisubstituted pyrimido[4,5-d]pyrimidine cyclin-dependent kinase (CDK2) inhibitors is designed and synthesized. 6-Amino-2-thiouracil is reacted with an aldehyde and thiourea to prepare the pyrimido[4,5-d]-pyrimidines. Alkylation and amination of the latter ones give different amino derivatives. These compounds show potent and selective CDK inhibitory activities and inhibit in ...

Despite their prevalence in organic synthesis, the application of boronic acids (BAs) as alkyl radical precursors visible-light-assisted photocatalyzed reactions has been limited by high oxidation potential. This study demonstrates prominent ability amide solvents, namely, N,N-dimethylacetamide, to participate hydrogen-bonding interactions with BAs, thus enabling modulation potential toward gen...

An operationally simple, mild, redox-neutral method for the photoredox alkylation of imines is reported. Utilizing an inexpensive organic photoredox catalyst, alkyl radicals are readily generated from the single-electron oxidation of ammonium alkyl bis(catecholato)silicates and are subsequently engaged in a C-C bond-forming reaction with imines. The process is highly selective, metal-free, and ...

Jobs on the side: Substrate selectivity studies indicate that members of the biomedically important JmjC demethylase family of histone N(ε)-methyllysine demethylases are capable of catalyzing the de-N-alkylation of groups other than N-methyl and can catalyze reactions that form stable hydroxylated products. The differences in binding preferences in this set of enzymes may be helpful in the desi...

Herein is reported the preparation of several series of polyammonium salts that serve as cationic lipids or precursors thereof, and are structurally based on the parent diamine 1,4-diazabicyclo[2.2.2]octane (dabco). Through selective alkylation of dabco a variety of di- and tetracationic lipid species and precursors thereof have been prepared. The resultant materials are of significant interest...

Aminooxyl sugar derivatives are versatile building blocks for the generation of various glycoconjugates with interesting bioactivities. We report herein a synthetic method for the preparation of orthogonally protected glycoaminooxy acid from methyl α-d-glycopyranoside in 7 steps. The key steps involve the selective protection, O-alkylation and Mitsunobu reaction. Fully deprotected N-oxyamide-li...

β-hydroxy aldehyde and alkyl ketone moieties were effectively synthesized as key intermediates of amphidinolide Q, a cytotoxic macrolide from the cultured dinoflagellate Amphidinium sp.. The asymmetric center of the former derivative was produced by Sharpless asymmetric epoxidation, followed by E-selective 1,4-addition to give the sp² methyl group. Derivatization of the L-ascorbic acid derivati...