alkyl: n-C 12 H 25 , n-C 16 H 33 , n-C 18 H 37 ) were synthesized and characterized. Their structure and purity were confirmed by means of 1 H and 13 C nuclear magnetic resonance analysis and electrospray ionization mass spectrometry. Carbon spectra were verified using a DEPT experiment. The surface and interfacial properties such as critical micelle concentration (CMC), standard free energy of micellization, ∆G CMC , surface excess concentration, Γ CMC , and surface area demand per molecule, A CMC , were determined. The tertiary nitrogen atom seems to have a surprising effect on surfactant packing at the interface.Materials. D(+)-Glucose δ-lactone, α-D-glucoheptonic γ-lactone, lactobionic acid, and alkylamines (n-dodecyl, n-hexadecyl, n-octadecyl) were purchased from Aldrich Chemical Co. (Milwaukee, WI). Other reagents and solvents were of commercial grade and were not additionally purified before use. Water used for all experiments was doubly distilled and purified by means of a Millipore (Bedford, MA) Milli-Q purification system.Synthesis of N-alkyl-N,N-bis(2-cyanoethyl)amines: typical procedure. To n-dodecylamine (92.7 g, 0.5 mol) in methanol

A new group of nonionic saccharide-based surfactants, N-alkanoyl-N-methyllactitolamines (alkanoyl: decanoyl, lauroyl, myristoyl, palmitoyl, stearoyl), were synthesized and characterized. Surface properties such as critical micelle concentration, standard free energy of adsorption, standard free energy of micellization, surface tension reduction efficiency, effectiveness of surface tension reduction, surface excess concentration, and surface area demand per molecule as well as foaming properties (i.e., foam volume and foam stability), contact angle, antimicrobial activity, and biodegradability were determined. The selected performance properties were evaluated in relation to commercially available alkyl polyglucosides (Glukopon 600 EC(HH)-a Henkel product), and oligooxyethylenated decyl (C 10 E 4 ) and dodecyl (C 12 E 5 ) alcohols. The foaming-stabilizing effect and contact angle suggest that the lactose-derived surfactants that were studied share some common properties with alkyl polyglucosides that are different from those with an oligooxyethylene grouping. All tested N-alkanoyl-N-methyllactitolamines were practically nontoxic to bacteria and yeasts. These compounds are readily biodegradable in the Closed Bottle test inoculated with activated sludge. N-Alkanoyl-N-methyllactitolamines with lower chain lengths (C 10 -C 14 ) biodegraded at a slightly faster rate. Biological properties showed that this class of compounds fulfills all requirements needed for environmental acceptance.Paper no. S1211 in JSD 4, 155-161 (April 2001).KEY WORDS: N-Alkanoyl-N-methyllactitolamines, antimicrobial activity, biodegradability, contact angle, foaming ability, nonionic lactose-derived surfactants, surface activity.Nonionic surfactants bearing a carbohydrate moiety as the hydrophilic part (so-called saccharide or sugar surfactants) have recently received increasing interest because they have improved surface and performance properties, reduced environmental impact, and they have potential pharmaceutical and biomedical applications (1-4). Because of these valuable features, many research groups have directed their studies to various aspects of synthetic methodologies and properties of a wide range of saccharide surfactants that vary in their molecular architecture, such as single-chain, single-head entities (5-12), di-chained (13,14) and dicephalic compounds (15,16) as well as bolaamphiphiles and gemini structures (17,18). Accordingly, all of these saccharide-derived materials exhibit similar general trends in surface-active behavior as reported for polyoxyethylene-based nonionics. However, the absence of a cloud point for aqueous solutions of saccharidebased nonionics indicates that the carbohydrate segments do not undergo dehydration with increasing temperature and that their interactions with water molecules are more favorable than the corresponding interactions between water molecules and polyoxyethylene segments. As a continuation of our studies (8,12,15,16) related to nonionic surfactants comprising various carbohydrate hydrop...

A new group of nonionics, so‐called sugar surfactants having a gemini structure, N,N′‐bisalkyl‐N,N′‐bis[(3‐gluconylamido)propyl]ethylenediamines [bis(CnGA): Cn=n‐C8H17, n‐C12H25], N,N′‐bisdodecyl‐N,N′‐bis[(3‐glucoheptonylamido)propyl]ethylenediamine [bis(C12GH)], and N,N′‐bisalkyl‐N,N′‐bis[(3‐lactobionylamido)propyl]ethylenediamines [bis(CnLA): Cn=n‐C8H17, n‐C12H25], were prepared in a convenient four‐step procedure from easily accessible reagents. Their structure and purity were confirmed by means of elemental analysis, electrospray ionization MS (ESI‐MS), and NMR spectra—1H, 13C, 1H−13C COSY, and distortionless enhancement by polarization transfer. All tested surfactants were practically nontoxic to gram‐negative bacteria and fungi, but they inhibited the growth of some gram‐positive bacteria. From the results of the Closed Bottle test (OECD Guideline 301D) for biodegradability measurements, it was concluded that the tested aldonamide gemini structures are biodegraded by environmental microorganisms to 16–55% of the initial levels by day 28, the extent depending on both the aldonamide type and the alkyl chain length. Consequently, N,N′‐bisalkyl‐N,N′‐bis[(3‐aldonylamido)propyl]ethylenediamines are a surfactant class having low ecotoxicity and fulfilling requirements desired from an ecological standpoint.

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