Transacylierungen mit Acylderivaten des 4‐Pyridons

A Convenient and Chemoselective Acetylation and Formylation of Alcohols and Phenols Using Acetic Acid and Ethyl Formate in the Presence of Bi(III) Salts

A variety of alcohols are acetylated and formylated efficiently with acetic acid and ethyl formate in the presence of catalytic amounts of Bi(III) salts such as BiCl3, Bi(TFA)3 and Bi(OTf)3. BiCl3 and Bi(OTf)3 are also effective catalysts for acetylation of phenols. All of these catalysts are ineffective in formylation of phenols. Selective acetylation and formylation of alcohols in the presence of phenols is an additional advantage of this procedure.

Safety Assessment of Ethanolamides as Used in Cosmetics

The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) rereviewed the safety of 28 ethanolamides and found them safe in the present practices of use and concentration when they are formulated to be nonirritating, and that these ingredients should not be used in cosmetic products in which N-nitroso compounds may be formed. Most of the ethanolamides are reported to function in cosmetics as hair-conditioning agents, skin-conditioning agents, and surfactant-foam boosters. The Panel reviewed available animal and clinical data, as well as information from previous CIR reports.

Mild and convenient N-formylation protocol in water-containing solvents

We have realized that N-formylations of free amines of some drug leads can improve PK/PD property of parent molecules without decreasing their biological activities. In order to selectively formylate primary amines of polyfunctional molecules, we have sought a mild and convenient formylation reaction. In our screening of N-formylation of an α-amino acid, L-phenylalanine, none of formylation conditions reported to date yielded the desired HCO-L-Phe-OH with satisfactory yield. N-Formylations of amino acids with HCO2H require the reactions in a water-containing media and suppress polymerization reactions due to the competitive reactions among carboxylic acids. We found that N-formylations of α-amino acids could be achieved with a water-soluble peptide coupling additive, an oxyma derivative, (2,2-dimethyl-1,3-dioxolan-4-yl)methyl-2-cyano-2-(hydroxyimino)acetate (2), EDCI, and NaHCO3 in water or a mixture of water and DMF system, yielding N-formylated α-amino acids with excellent yields. Moreover, these conditions could selectively formylate primary amines over secondary amines at a controlled temperature. A usefulness of these conditions was demonstrated by selective formylation of daptomycin antibiotic which contains three different amino groups.