2- ethyl phosphate groups

The H-NMR spectrum of 6 shows resonances at S 1.03 and 1.38 for the terf-butyl groups in the ratio of 2 1, and a single multiplet for the methylenes at 5 4.64. These data support the structure shown where pairs of oxygens across the lower rim are bridged, and do not support a structure where adjacent pairs of phenolic groups around the lower calix[6]arene rim are sequentially spanned by ethyl phosphate groups. 

A new class of zwitterionic phospholipids (iPCs) (36), with an inverted headgroup charge orientation relative to traditional phosphocholine (37) lipids have been described by Szoka and co-workers. Neutral iPC lipids with ethylated phosphate groups (36a) and anionic iPC lipids with non-ethylated phosphate groups (36b) have been obtained. The iPC lipid head... 

Aminoacyl adenylates (296), which are formed from protein amino acids and ATP, act as acylating agents towards t-RNAs, acylating their terminal 3 -hydroxy groups. These charged tRNAs are then used in protein synthesis. Little is known about the reactivity of aminoacyl adenylates (296), and studies are now reported of a model compound, alanyl ethyl phosphate (297). As expected, hydrolysis in both acid and base involves attack at the C=0 group of (297) with departure of ethyl phosphate. Metal ions (Cu +, Zn +) were found to act as catalysts of the hydrolysis. 

The 2-(methyldiphenylsilyl)ethyl (DPSME) group was used to protect a phosphate in a synthesis of Lysobisphosphatidic Acid [Scheme 7.40].82 The phosphate protection was introduced by a phosphite triester approach to give the symmetrical phosphate 40 2. The two isopropylidene groups were removed by acid hydrolysis without harm to the phosphate and the resultant diols selectively protected on their less hindered termini with fert-butyldiphenylsilyl groups. Acylation of the remaining secondary hydroxyls with oleic anhydride afforded the diester 403, whereupon the silyl protecting groups were removed with... 

Bisphenol A (chemically similar to MDA but having -OH groups rather than amine groups) was identified in the water and 3% acetic extracts from Sample 2. Bisphenol A was not detected in the extracts from Sample 1. Infrared transmission spectra recorded through Samples 1 and 2 showed that the MDl isocyanate was slower to react in Sample 2 and so the bisphenol A could possibly relate to the laminating adhesive. As a result, LC-MS tests were undertaken later in the research, on extracts from Sample 3 (laminated with the same adhesive) specifically looking for bisphenol A - none was detected. Tri-ethyl phosphate, thought to be used as a cure catalyst, was identified in the extracts from both Sample 1 and Sample 2. 

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