FRAGMENTATION OF A PHENYLPHOSPHONAMIDIC ACID AS A NEW TECHNIQUE FOR THE GENERATION OF PHENYL DIOXOPHOSPHORANE
摘要:
N-(1-Adamantyl) phenylphosphonamidic acid (3), an easily prepared solid, on heating in toluene or 1,2-dichloroethane gave the crystalline adamantylamine salt of the anhydride PhP(O)(NHAd)-O-PPh(O)(OH). The mechanism is proposed to involve first the fragmentation of 3 to form phenyl dioxophosphorane, PhPO(2), which then acts as a phosphorylating agent to unreacted 3. This mechanism was supported by the observation of first-order kinetics for the consumption of 3. When the phosphonamidic acid was fragmented in the presence of an alcohol, the intermediate PhPO(2) was trapped as the monoalkyl phenylphosphonate. The OH groups on the surface of silica gel were also phosphonylated by PhPO(2). The acidic OH group of a phosphoric acid monoester (thymyl phosphate) was phosphonylated to give Thy-O-P(O)(OH)-O-PPh(O)(OH). It is concluded from this study that N-(1-adamantyl) phenylphosphonamidic acid is a useful precursor of phenyl dioxophosphorane, which can perform valuable phosphonylation operations.
Generation of Ethyl Metathiophosphate by Thermal Fragmentation of <i>O</i>-Ethyl <i>N</i>-Substituted Phosphoramidothioates
作者:Louis D. Quin、Petr Hermann、Stefan Jankowski
DOI:10.1021/jo952270j
日期:1996.1.1
and found to fragment on heating in inert solvents to form the pyrophosphate AdNHP(S)(OEt)OP(S)(OEt)OH. The proposed mechanism involves an elimination of the amine portion with release of ethyl metathiophosphate (EtOP(S)O), as was confirmed in previous work for the comparable structure with oxygen. This transient compound then phosphorylates the starting phosphoramidothioate. O-Ethyl N,N-diethylphosphoramidothioate
The present invention relates to a method for inhibiting an undesirable taste in oral compositions such as foods, beverages, dental compositions, and pharmaceuticals. The present invention also relates to oral and pharmaceutical compositions comprising undesirable tasting compounds wherein undesirable tastes are inhibited by the addition of an inhibitor of intracellular phosphatase enzymes of taste cells to said oral and pharmaceutical compositions. Said inhibitor is selected from phosphates, thiophosphates, phosphonates, vanadates, bisphosphates, bisphosphonates, phosphate-phosphonates, thiophosphate-phosphates, thiophosphate-phosphonates, their physiologically-relevant salts and esters, and mixtures thereof.