Synthesis of diethanolamides of N‐lauroyl dipeptides and correlation of their structures with surfactant and antibacterial properties

Abstract

643 DiethanolRmides (DEA) of proteins possess nonionic skincompatible, biodegradable, surfactant and antibacterial properties. The DEA of dipeptides are, however, too hydrophilic to be effective surfactants. Hence, DEA of N-lauroyl dipeptides were synthesized and their surfactant and antibacterial properties were correlated with the structures of Amino acid moieties. N-Lauroyl condensates of five simple Amluo acids were coupled with the cop responding Amino acid methyl esters and the resulting products were condensed with diethanolamine in the presence of sodium methoxide to yield DEA of N-lauroyl dipeptides. The DEA of N-lauroyl glycine dipeptide showed surfactant properties comparable to lauroyl diethanol-Rmlde. The thiol group in the cysteine derivative exerted an unfavorable effect on surfactant properties. The isobutyl side chain in the leucine derivative contributed greatly to the antibacterial activity when compared to the other amino acid derivatives studied. KEY WORDS: Diethanolamides of N-lauroyl dipeptides, structure vs. surfactant and antibacterial properties.

Synthesis and Properties of Three N‐Alkyl Bis‐Quaternary Ammonium Salt Surfactants

“…That enhances the pressure of the bacterial cell wall, destroys the integrity of the bacterial membrane, and weakens its barrier function. Besides, long‐chain alkyls penetrate into their cell membranes, causing diarrhea in the membrane, while also inactivating protein on the cell wall, ultimately leading to bacterial death (Mhaskar and Lakshminarayana, 1992; Richardson et al, 2013). Normally, the length of hydrophobic chain has impact on the antimicrobial activity of cationic surfactants.…”

N‐acyl‐L‐leucines of biologically active uncommon fatty acids: Synthesis and antibacterial activity

“…For the synthesis of N-[5-trans-octadecen-7,9-diynoyl] leucine (3), the fragment 5-trans-octen-7-ynol (1) was synthesized as described by us (7) for use as starting material. For N-[6-hydroxy-7,9-octadecadiynoyl] leucine (6) and N-[6-(R)-hydroxy-7,9-octadecadiynoyl] leucine (6a), the fragments 6-hydroxy-7-octynol (4) and its R-enantiomer (4a) were synthesized, respectively, for use as starting materials (8). Analytical-grade reagents required for the synthesis were purchased from Aldrich Chemical Co. (Milwaukee, WI).…”

“…The synthesis of N-acyl-L-leucines of some uncommon fatty acids and correlation of the acyl structure with antibacterial activity form the subject of the present communication. We have selected IAeucine as the amino acid moiety because it showed the highest antibacterial activity of the diethanolamides of lauroyl dipeptides for five simple amino acid~ namely glycin~ leucin~ phenylalanin~ proline and cysteine (6). The uncommon fatty acids coupled with leucine were: 1,9-nonanedicarboxylic (azelaic), 9-octadecynoic (stea~ olic), 9,10-oxiraneoctadecanoic (9,10-epoxystearic), 9,10methyleneoctadecanoic (dihydrosterculic), 5-trans-octade ~ cen-7,9<liynoic (7), 6-hydroxy-7,9~ctadecynoic (Mhaskar, SY., unpublished data) and its R-isomer (8) ( Table 1).…”

Phases and phase transition in insoluble and adsorbed monolayers of amide amphiphiles: Specific Characteristics of the condensed phases

“…In addition, ethanolamine is also the structural component of N -acylethanolamines (NAEs), N-,Odiacylethanolamines (DAEs) [4] and N -acylphosphatidylethanolamines (NAPEs), which are present in a wide variety of organisms. Therefore, the amphiphilic derivatives of ethanolamine found special interest not only because of their occurrence in a wide variety of animals, plants, and microbes [3,5] but also due to their interesting biological, pharmaceutical, and medicinal properties [6][7][8][9]. Because of a number of interesting biological and medicinal properties, NAEs have been of permanent interest.…”