Hydration derivs

Midrin is a proprietary combination of acetaminophen, isometheptene mucate (a sympathomimetic amine), and dichloralphenazone (a chloral hydrate derivative) that has shown modest benefits in placebo-controlled trials. It may be an alternative for patients with mild to moderate migraine... 

Pt(II) compound reactivation, 37 201 Pt(IV) compound reduction, 37 201 rate-determining step, 37 199-201 tetrachloride, 4 187-188 tetracyanide anions, as one-dimensional electrical conductors, 26 235-268 anion-deficient structures anhydrous compounds, 26 252-254 dimerization, 26 249-251 hydrated derivatives, 26 245-252 physics, 26 260-263 with potassium bromide, 26 248-249 with rubidium chloride, 26 249-250 cation-deficient compounds, 26 244, 254-256... 

The neutral species of this parent is completely hydrated in aqueous solutions45 whereas pteridine is only 20% hydrated under the same circumstances in accord with its less electron-depleted 7r-layer. Hydrated derivatives of 7-azapteridine have since been noted.46 It has been claimed that 2-chloro-4-ethoxycarbonyl-7-azapteridine forms a 1,2-monohydrate in which the hydroxyl group and the chlorine are attached to C-2. This very unusual type of hydrate spontaneously isomerizes to the 3,4-monohydrate.47... 

The familiar phosphoric acid, H3P04 (melting point, 43° C), is more specifically orthophosphoric acid, as distinct from pyrophosphoric acid, (OH)sP—O—P(OH)2, and from the less hydrated derivatives of... 

Hydroxyisoindolines (217) are polarographically reducible226 as would be expected because they are derivatives of an aromatic aldehyde. As other hydrated derivatives of carbonyl or azomethine compounds they must lose water before electrons can be accepted the reduction proceeds through a radical. 

Kessler J., Reeburgh W., Southon J., and Tyler S. (2(X)3) Natural radiocarbon in Black Sea water column methane a tracer of hydrate-derived methane EGS/AGU/EUG abstracts, 5, 12216, Apr. 6-11, Nice, Erance. 

Semiempirical calculations of free energies and enthalpies of hydration derived from an electrostatic model of ions with a noble gas structure have been applied to the ter-valent actinide ions. A primary hydration number for the actinides was determined by correlating the experimental enthalpy data for plutonium(iii) with the model. The thermodynamic data for actinide metals and their oxides from thorium to curium has been assessed. The thermodynamic data for the substoicheiometric dioxides at high temperatures has been used to consider the relative stabilities of valence states lower than four and subsequently examine the stability requirements for the sesquioxides and monoxides. Sequential thermodynamic trends in the gaseous metals, monoxides, and dioxides were examined and compared with those of the lanthanides. A study of the rates of actinide oxidation-reduction reactions showed that, contrary to previous reports, the Marcus equation ... 

In the cell, an area of low chloride ion concentration, equilibrium favors loss of the anionic ligands with the formation of various hydrated derivatives. It is these very reactive complexes, with their labile aquo ligands, which coordinate to DNA and lead to the observed cytotoxicity. Excepting considerations of solubility, the broad structure/activity observations of the past decade are probably a reflection of variations in only the end of this process. In particular, variations in the amine identity are likely to have only minor effects on the kinetics... 

Related to the aluminas, especially the /3-aluminas, are tricalcium aluminate and its hydrated derivatives. These are major components of Portland cement and of high-alumina cement. A structural modification and the heat released on hydration are factors in the setting process of these cements. 

Sn 1-active alkyl halides require longer reaction times (typically 3-6 h), and the yields are lower. f-Butyl chloride and adamantyl bromide have been used successfully, but the generality of the procedure needs to be demonstrated (eq 4). In contrast, acylation reactions using a wide variety of carboxylic acid chlorides have been carried out (eq 5). The initial products are protected forms of Q ,/3-diketo esters which can be isolated in yields of 72-93%. Deprotection is accomplished using MeOH/HCl. The products are vicinal tricarbonyl compounds having the usual characteristic chemical properties such as rapid formation of hydrated derivatives. The protected forms can be used directly in the synthesis of heterocycles. ... 

Formation of Symmetrical Anhydrides. Symmetrical carboxylic anhydrides are useful reagents for peptide or amide synthesis. Unfortunately, most methods require transformation of the acid first into the acid chloride or the use of condensation agents, e.g. 1,3-Dicyclohexylcarbodiimide (DCC), which can lead to separation problems of the product anhydride from the hydrated derivatives of the condensation reagents. The use of Thionyl Chlo-ridelPyridine to form the acid chloride is often complicated by racemization with amino acid derivatives. 

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