13 Fast-absorbing gut is heat treated also to create more rapid absorption than chromic gut. Chromic gut is absorbed more rapidly than PGA on the oral mucosa and does not require suture removal. Wounds within the oral cavity tend to heal rapidly and do not require prolonged suture support. 11,12 Because of its relatively rapid absorption, the main use of chromic gut is to close lacerations within the oral mucosa, perineum, and scrotal skin. Compared with PGA, plain gut and chromic gut appear to have inferior tensile strength and wound security.
A newer form of this suture is gut treated with chromium trioxide (chromic gut) to retard absorption in tissues however, its holding security is only 14 days. Gut is an organic material manufactured from sheep intestines. Trott MD, in Wounds and Lacerations (Fourth Edition), 2012 Gut (Plain, Chromic, Fast-Absorbing)Īn older and less commonly used absorbable suture material is gut. The anhydride also undergoes a Perkin condensation with aromatic aldehydes in the presence of a base to give 1-oxo-3-phenylisochroman-4-carboxylic acids 〈58JCS2612〉.Īlexander T. Reduction of these half esters yields isochroman-1-ones. Methyl 2-carboxyphenylacetates are formed by methanolysis of homophthalic anhydrides. The direct oxidation of 2-(2-hydroxymethylphenyl)ethan-1-ols to isochroman-1-ones may proceed via the isochroman 〈61TL223〉. When the 1-position is fully substituted, oxidation takes place at C-4 using a variety of oxidants 〈69BSF915〉. Chromium trioxide is reported to be better than selenium dioxide 〈62JOC4337〉 and potassium permanganate in acetone is also recommended 〈59JCS3598〉. Oxidation of the 1-methylene group of isochroman occurs on reaction with selenium dioxide to give isochroman-1-one 〈56BSF1337〉. Hepworth, in Comprehensive Heterocyclic Chemistry, 1984 2.24.3.7.7.(iii) From a preformed heterocyclic ring 2.24.3.7.7.(iii).(a) From isochromans 40 The use of sodium hypochlorite as cooxidant in the oxidation of the bicyclic ketone ( 5) led preferentially to the formation of the Baeyer–Villiger product ( 6), whereas sodium periodate gave the lactone ( 7 Scheme 1) 41 Similar results were obtained in a later study using catalytic ruthenium chloride and sodium or calcium hypochlorite as the stoichiometric oxidant under phase transfer conditions. When the two-phase catalytic method was employed, however, reaction times were long, and products unstable to aqueous conditions tended to undergo further oxidation to the corresponding carboxylic acids (equations 9 and 10).
Chromium trioxide series#
Good yields of esters and lactones were obtained from a series of simple ethers using the stoichiometric method (equations 7 and 8). 39 In the latter case, catalytic quantities of the reagent were generated by vigorously stirring a mixture of ruthenium dioxide in carbon tetrachloride with an aqueous solution of sodium periodate at room temperature. In 1980, Smith and Scarborough published details of a systematic study of ether oxidation by ruthenium tetroxide in which they compared the relative merits of both the stoichiometric and the two- phase catalytic methods. The general acceptance of the reagent as a powerful wide-ranging oxidant, 38 coupled with the expense of ruthenium metal, however, later provided the incentive to develop alternative catalytic procedures. Reactions were carried out at room temperature. Much of the early work with ruthenium tetroxide also made use of stoichiometric amounts of a solution of the reagent in an inert solvent, such as carbon tetrachloride.
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