Iodine synthesis

G. Siewert and O. Westphal, Substitution of secondary p-tolylsulfonyloxy groups by iodine. Synthesis of 4-deoxy- and 4,6-dideoxy-D-xylo-hexose, Liebigs Atmalen der Chemie 720 161... 

Kamber, B. (1971) Cystine peptides from (S-acetamidomethyl-cysteine)-peptides through oxidation with iodine synthesis of cyclo-L-cystine. Helv. Chem. Acta 54, 927-930. 

Intramolecular Cyclization of cis-cis-l,5-Cyclooctadiene Using Hypervalent Iodine Synthesis of B1cyclo[3.3.0]octa-2,6-dione R. H. Moriarty, M. P. Ducan, 0. Prakash, and R. K. Vaid, Department of Chemistry, University of Illinois at Chicago, Chicago, IL 606B0... 

Iodine Synthesis of thyroxin lack leads to goiter... 

Hypervalent Iodine Synthesis of Bicyc1o[3.3.0]octa-2,6-dione... 

Wolff, J., Chaikoff, I.L., Goldberg, and Meier, J.R., The temporary nature of the inhibitory action of excess iodide on organic iodine synthesis in thenormal thyroid. Endocrinology 45 504 (1949). 

Fang X, Tang R, Zhong P, Li J. Iron-catalyzed sulfenylation of indoles with disulfides promoted by a catalytic amount of iodine. Synthesis 2009 4183 189. 

Metabolic Functions. The functions of the thyroid hormones and thus of iodine are control of energy transductions (121). These hormones increase oxygen consumption and basal metaboHc rate by accelerating reactions in nearly all cells of the body. A part of this effect is attributed to increase in activity of many enzymes. Additionally, protein synthesis is affected by the thyroid hormones (121,122). 

The synthesis of poly(arylene sulfide)s via the thermolysis of bis(4-iodophenyl) disulfide has been reported (78). The process leads to the formation of PPS and elemental iodine. This process presumably occurs analogously to that reported by Eastman Chemical Company. 

High Osmolality Contrast Media. An important advance in radiopaques came with the synthesis of aminotriiodoben2oic acid and its acetylated derivative, acetrizoic acid [85-36-9] (5) (8,9). Aqueous solutions of sodium acetrizoate possessed the thermal stabiUty so that they could be autoclaved (10) with minimal decomposition. The higher iodine content, ie, 3 atoms/molecule, increased the contrast efficiency, and the clinical safety of acetrizoate was improved over that of the earlier urographic agents. 

The steric bulk of the three iodine atoms in the 2,4,6-triiodoben2ene system and the amide nature of the 1,3,5-substituents yield rotational isomers of the 5-A/-acyl-substituted 2,4,6-triiodoisophthalamides. Rotational motion in the bonds connecting the side chains and the aromatic ring is restricted. These compounds also exhibit stereoisomerism when chiral carbon atoms are present on side chains. (R,5)-3-Amino-l,2-propanediol is incorporated in the synthesis of iohexol (11) and ioversol (12) and an (3)-2-hydroxypropanoyl group is used in the synthesis of iopamidol (10). Consequendy, the resulting products contain a mixture of stereoisomers, ie, meso-isomers, or an optical isomer. 

Synthesis. In the syntheses of T and its congeners, formation of the stericaHy hindered diaryl ether core is difficult, as is the introduction of the alanyl side chain (or the preservation of its L (3) absolute configuration) and iodination to the desired degree (T or T. ... 

Sodium Levothyroxine. As one of the active principles of the thyroid gland, sodium levothyroxine [55-03-8] (levothyroxine sodium) can be obtained either from the thyroid glands of domesticated animals (10) or synthetically. It should contain 61.6—65.5% iodine, corresponding to 100 3% of the pure salt calculated on an anhydrous basis. Its chiral purity must also be ascertained because partial racemi2ation may occur during synthesis and because dl-T is available commercially. Sodium levothyroxine melts with decomposition at ca 235°C. It is prepared as pentahydrate [6106-07-6] from... 

If bromine is used in equation 8, carbon tetrabromide [558-13-4] is formed. With a minor amount of iodine present, and in the absence of iron catalyst, carbon disulfide and chlorine react to form trichioromethanesulfenyl chloride (perchloromethyl mercaptan [594-42-3]), CCI3SCI, which can be reduced with staimous chloride or tin, and hydrochloric acid to form thiophosgene (thiocarbonyl chloride [463-71-8], CSCI2, an intermediate in the synthesis of many organic compounds (see Sulfurcompounds). 

Fluorination and iodination reactions are used relatively littie in dye synthesis. Fluorinated species include the trifluoromethyl group, which can be obtained from the trichi oromethyl group by the action of hydrogen fluoride or antimony pentafluoride, and various fluorotria2iQyl and pyrimidyl reactive systems for reactive dyes, eg, Cibacron F dyes. 

Hyperthyroidism may be treated in several ways. One of these is interference with the synthesis of the thyroid hormones, possibly by removal of iodine. Thiourea and cyclic thioureas have this effect and of such cyclic compounds, thiouracil (1030 R = H), its 6-alkyl derivatives (1030 R = Me or Pr) and thiobarbital (1031) are effective thyroid drugs. Today only propylthiouracil (1030 R = Pr) is widely used, probably because it has fewer side effects than the others (71MI21302). The thiouracils are made by the Principal Synthesis from a /3-oxo ester (1032 R = H, Me, Pr, etc.) and thiourea (45JA2197) their fine structures are experimentally based (64AF1004). 

Fluorinated and iodinated derivatives are usually prepared by halogen exchange reactions, although the Baltz-Schiemann reaction has been applied to the synthesis of 2-fluoroquin-oxaline (66JHC435>. 

Acrylic acid, -(3-benzo[f>]thienyl)-a -mercapto-reaction with iodine, 4, 764 Acrylic acid, o -cyano-y3-(2-thienyl)-ring opening, 4, 807 Acrylic acid, -formyl-in pyridazinone synthesis, 3, 46 Acrylic acid, furyl-rotamers, 4, 545 synthesis, 4, 658 Acrylic acid, 2-hydroxybenzoyl-chroman-4-one synthesis from, 3, 850 Acrylic acid, 5-(l-propynyl)-2-thienyl-methyl ester occurrence, 4, 909 Acrylonitrile... 

Cinnolin-4(lH)-one, 8-hydroxy-iodination, 3, 21 Cinnolin-4-ones synthesis, 3, 56 Circular dichroism indolizidines, 4, 450 pyridines and benzo derivatives, 2, 126... 

Imidazole, 4,5-dibromo-l-methyl-synthesis, S, 399 Imidazole, 4,5-di-t-butyl-synthesis, S, 483 X-ray diffraction, S, 350 Imidazole, 4,5-dichloro-chlorination, S, 398 synthesis, S, 398, 473 Imidazole, 4-(3,4-dichlorophenyl)-nitration, 5, 433 Imidazole, 4,5-dicyano-hydrolysis, S, 435-436 synthesis, S, 461, 472, 487 Imidazole, 4,5-dicyano-1-vinyl-synthesis, S, 387 Imidazole, 4,5-dihydro-mass spectra, 5, 360 Imidazole, 4-(dihydroxybutyl)-synthesis, S, 484 Imidazole, 4,5-diiodo-nitration, S, 396 synthesis, S, 400 Imidazole, 2,4-diiodo-5-methyl-iodination, S, 400 Imidazole, 1,2-dimethyl-anions... 

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