Efficient synthesis of bolaform- and gemini-type alkyl-bis-[(α-amino)phosphonocarboxylic or phosphonic acid] surfactants

Synthetic strategies of phosphonodepsipeptides

Phosphonodepsipeptides are phosphorus analogues of depsipeptides and phosphonate-linked analogues of naturally occurring peptides. They are more stable than phosphonopeptides and have been widely applied as enzyme inhibitors, haptens for the production of antibodies, biological agents, and prodrugs. The synthetic strategies towards phosphonodepsipeptides are reviewed, including the phosphonylation of hydroxy esters with phosphonochloridates, the condensation of phosphonic monoesters and hydroxy esters, the alkylation of phosphonic monoesters with 1-(alkoxycarbonyl)alkyl halides or sulfonates, multicomponent condensation of amides, aldehydes, and dichlorophosphites followed by alcoholysis with hydroxy esters, the phosphinylation of hydroxy esters with phosphonochloridites followed by oxidation, and the carbene insertion of N-protected amino acids with 1-diazoalkylphosphonates. This review includes the synthesis of α-, β-, and γ-phosphonodepsipeptides and phosphonodepsipeptides with C-1-hydroxyalkylphosphonic acids.

Synthesis of a Bolaamphiphilic Alkenyl Phosphonic Acid by Ru-catalyzed Olefin Cross Metathesis Reaction

We report the synthesis of bolaamphiphilic alkenyl phosphonic acid (BPC₁₂) through the olefin crossmetathesis reaction of vinylphosphonic acid with 1,11-dodecadiene in the presence of a Ru-carbene catalyst. BPC₁₂ possesses two trans-P-C=C moieties and is thus readily soluble in water up to 3.4 g L^-1, as confirmed by ¹H nuclear magnetic resonance (NMR) measurements. Surface tension measurements revealed that BPC₁₂ reduced the surface tension of water from 72.0 to 47.0 mN m^‒1. The occupied area per molecule at the air/water interface (A) of BPC₁₂ (216 Ų) was ten times larger than that of dodecenyl phosphonic acid PC₁₂ (23 Ų). Moreover, dynamic light scattering measurement of an aqueous BPC₁₂ solution (5 mM) revealed the formation of large aggregates with an average diameter of 81.8±27.0 nm.