629-98-1Relevant articles and documents
Enantiomeric synthesis of natural alkylglycerols and their antibacterial and antibiofilm activities
Fernández Montoya, Deicy J.,Contreras Jordan, Luis A.,Moreno-Murillo, Bárbara,Silva-Gómez, Edelberto,Mayorga-Wandurraga, Humberto
supporting information, p. 2544 - 2550 (2019/11/13)
Alkylglycerols (AKGs) are bioactive natural compounds that vary by alkyl chain length and degree of unsaturation, and their absolute configuration is 2S. Three AKGs (5l–5n) were synthesised in enantiomerically pure form, and were characterised for the first time together with 12 other known and naturally occurring AKGs (5a–5k, 5o). Their structures were established using 1H and 13C APT NMR with 2D-NMR, ESI-MS or HRESI-MS and optical rotation data, and they were tested for their antibacterial and antibiofilm activities. AKGs 5a–5m and 5o showed activity against five clinical isolates and P. aeruginosa ATCC 15442, with MIC values in the range of 15–125 μg/mL. In addition, at half of the MIC, most of the AKGs reduced S. aureus biofilm formation in the range of 23%–99% and P. aeruginosa ATCC 15442 biofilm formation in the range of 14%–64%. The antibiofilm activity of the AKGs assessed in this work had not previously been studied.
Highly chemoselective reduction of amides (primary, secondary, tertiary) to alcohols using SmI2/amine/H2O under mild conditions
Szostak, Michal,Spain, Malcolm,Eberhart, Andrew J.,Procter, David J.
supporting information, p. 2268 - 2271 (2014/03/21)
Highly chemoselective direct reduction of primary, secondary, and tertiary amides to alcohols using SmI2/amine/H2O is reported. The reaction proceeds with C-N bond cleavage in the carbinolamine intermediate, shows excellent functional group tolerance, and delivers the alcohol products in very high yields. The expected C-O cleavage products are not formed under the reaction conditions. The observed reactivity is opposite to the electrophilicity of polar carbonyl groups resulting from the nX → πC=O (X = O, N) conjugation. Mechanistic studies suggest that coordination of Sm to the carbonyl and then to Lewis basic nitrogen in the tetrahedral intermediate facilitate electron transfer and control the selectivity of the C-N/C-O cleavage. Notably, the method provides direct access to acyl-type radicals from unactivated amides under mild electron transfer conditions.
Synthesis and solution properties of cationic gemini surfactants with long unsaturated tails
Li, Huazhen,Yang, Haiyang,Yan, Yunfei,Wang, Qin,He, Pingsheng
experimental part, p. 1173 - 1178 (2010/08/21)
Gemini surfactants 22:1-s-22:1, where s = 2 and 6 methylene groups and 22:1 refer to erucyl dimethylammonium bromide chains, together with the monomeric surfactant erucyl bis-(hydroxyethyl) methylammonium bromide (EHAB) which has the same long unsaturated tails with gemini surfactants, were synthesized and characterized and solution properties of these surfactants were investigated using surface tension, conductivity and viscosity measurement. It has been found that the critical micelle concentration (cmc) values of 22:1-2-22:1 and 22:1-6-22:1 are 15.4 and 8.3 μM, respectively, less than the cmc value of EHAB (38 μM). On the other hand, the surface tension of 22:1-2-22:1 and 22:1-6-22:1 at cmc are 40.9 and 42.4, respectively, greater than the surface tension of EHAB (30.9 at cmc). Both 22:1-2-22:1 and 22:1-6-22:1 have nearly the same value of a0 (the minimum head group areas per surfactant molecule at the aqueous solution/air interface), which is almost the half value of a0 corresponding to EHAB. On the other hand, the ionization degree α of micelles of both 22:1-2-22:1 and 22:1-6-22:1 is approximately twice the value of α corresponding to micelles of EHAB. Though 22:1-2-22:1 has more similarity with 22:1-6-22:1 rather than EHAB as presented above, 22:1-2-22:1 in water cannot enhance the viscosity of the solution significantly in the presence of salt. In contrast, both 22:1-6-22:1 and EHAB in water can give rise to highly viscoelastic or gel-like solutions even at the high temperature in the presence of salt. In particular, 22:1-6-22:1 has proved to be a more efficient candidate for high temperature rheology-control applications than EHAB. The effect of salt upon the viscosity of 22:1-6-22:1 in aqueous solution is significant. The most proper ratio of 22:1-6-22:1/NaSal for enhancing the viscosity of solution has been proved to be 0.7.
