Tion . . 56 partial hydrolysis

A very significant mortality in Western countries is associated with cardiac arrhythmias Consequently an intensive search is underway for agents to combat this condition - particularly for compounds with an unusual mode of action A class Ic (local anesthetic-like) agent of interest in ihis context is Indecainide (50) One of several routes to this compound covered by patents begins with sodium amide mediated alkylation of 9 cyanofluorene (48) with 3 isopropylamino-1 chloropropane to give amine 49 The synthesis concludes by partial hydrolysis of the nitnle func tion to a carboxamide linkage with sulfunc acid to produce indecainide (50) [15]... 

Although these synthetic routes are effective, some problems were observed in the last reaction step. Spectroscopic and elemental analysis indicated that the nickellation of the pincer moiety was incomplete, giving an average of 80 to 90% of metallated pincer sites per dendrimer. This observation was rationalized by partial hydrolysis of the reactive lithiated species prior to the introduction of the nickel reagent, causing incomplete metalla-tion of the ultimate dendrimer species [37,38]. 

Maltose, C12H22O11.H2O, is formed as the result of the action upon starch of the diastase in malt, the ptyalin in saliva, and other ferments, and in the partial hydrolysis of starch and dextrin by acids. It is present in commercial glucose, in beer, and probably in bread. It is manufactured on the large scale in the preparation of alcohol and alcoholic beverages (59). Maltose crystallizes from water, in which it is readily soluble, in plates, which contain one molecule of water of crystallization. It is obtained from alcohol in wart-like aggregates which are anhydrous. Maltose is dextrorotatory, and shows mutarota-tion for the anhydrous form [a]jy = 137°. 

Sodium alginate...Sodium alginate(Wako Pure Chemical Industries, Ltd) was obtained commercially. This was named CM or sample 1. G/M of sample 1 is ca.0.91 and DP is 468-473. From sample 1 insoluble frac-tion(degraded one, sample 2), pH 2.85(G-rich, sample 3), pH 1.5(M-rich, sample 4), G(pure G, sample 5) and M(pure M, sample 6) were obtained by partial hydrolysis vjith IM oxalic acid and by anion exchange chromatography. 

A synthetically useful virtue of enol triflates is that they are amenable to palladium-catalyzed carbon-carbon bond-forming reactions under mild conditions. When a solution of enol triflate 21 and tetrakis(triphenylphosphine)palladium(o) in benzene is treated with a mixture of terminal alkyne 17, n-propylamine, and cuprous iodide,17 intermediate 22 is formed in 76-84% yield. Although a partial hydrogenation of the alkyne in 22 could conceivably secure the formation of the cis C1-C2 olefin, a chemoselective hydrobora-tion/protonation sequence was found to be a much more reliable and suitable alternative. Thus, sequential hydroboration of the alkyne 22 with dicyclohexylborane, protonolysis, oxidative workup, and hydrolysis of the oxabicyclo[2.2.2]octyl ester protecting group gives dienic carboxylic acid 15 in a yield of 86% from 22. 

See Section IV.1 for alternative methods of chiral resolution. Partial chemical hydrolysis of proteins and peptides with hot 6 M HC1, followed by enzymatic hydrolysis with pronase, leucine aminopeptidase and peptidyl D-amino acid hydrolase, avoids racemiza-tion of the amino acids281. The problems arising from optical rotation measurements of chiral purity were reviewed. Important considerations are the nonideal dependence of optical rotation on concentration and the effect of chiral impurities282. 

Unlike the other addition polymers described here, PVOH is not prepared from its corresponding monomer, since vinyl alcohol does not exist as a monomer due to tautomerisa-tion to acetaldehyde. However, the polymer can be produced by polymerisation of vinyl acetate followed by partial (85-90%) to complete (>97%) hydrolysis of the acetate groups. In both these cases the product is completely water soluble, although the use of PVOH as a primary thickener is rather limited due to the relatively low molecular weight which is obtained in the preparation of the corresponding polyvinyl acetate. Hydrophilic gels can be obtained when solutions of PVOH are mixed with sodium tetraborate. 

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