Thymidine carboxylic acids

Montevecchi PC, Manetto A, Navachhia ML, Chatgilialoglu C (2004) Thermal decomposition of the tert-butyl perester of thymidine-5 -carboxylic acid. Formation and fate of the pseudo-C4 radical. Tetrahedron 60 4303-4308... 

Methyl-2 -deoxycytidine (437) and 3-methyl-2 -deoxyuridine (438) were isolated from the Swedish sponge Geodia baretti. Compound 437 exhibits strong contractile activity in the isolated guinea pig ileum assay, whereas 438 had no effect on contractions (356). Thymidine-5 -carboxylic acid (439) and 2 -deoxyuridine-5 -carboxylic acid (440), which were previously known only as synthetic products, were found in extracts of the ascidian Aplidium fuscum of the East Pyrenean coast (357). 

The crystal structure of thymidine 5 -carboxylic acid [TYMCXA] is unusual in that it has two molecules in the asymmetric unit with almost identical hydrogenbonding schemes related by a noncrystallographic pseudo-twofold axis of symmetry. In Fig. 17.30, data for molecule A given without, those for molecule B with... 

The monomers, (R)-(-)-uracil-l-yl-2,3-dihydrofliian la and (R)-(-)-2-thymin-l-yl-2,3-dihydrofuran Ib were synthesized according to Zemlicka s methods - which involved oxidation of 2-deoxyuridine and tlqmiidine followed by decarboxy dehydration of the resulting 2 -deoxyuridine-5 -carboxylic acid and thymidine-5 -carboxylic acid. 

The method used to convert adenosine-5 -carboxylic acid to (I) and (II) did not convert uridine- or thymidine-5 -carboxylic acids to the analogous UMP or TMP carboxylic-phosphoric anhydrides. 

Thymidine-5 -carboxylic acid and dimethylformamide dineopentyl acetal in dimethylformamide heated 4.5 hrs. at 80-90° l-(2, 3 -dideoxy-3, 4 -didehydro-) -D-erythrofuranosyl)thymine. Y 94%. - This reaction comprises a useful selective degradation of C-5 from a 2 -deoxynucleoside. F. e. s. J. 2emliSka et al.. Am. Soc. 94, 3213 (1972). 

C10H12N2O6, Thymidine 5 -carboxylic acid, 40B, 415 Cl Hi 2N4O1, Hypoxanthine-8-(2 -desoxy-riboside), 4IB, 513 C10H12N4O4, Nebularine, 40B, 416 C10H12N4O4S, 6-Thiopurine riboside, 33B, 170... 

A.7.1 Esterification of Acids using Carbodiimides. The formation of anhydrides from carboxylic acids, thiocarboxylic acids, sulfonic acids and phosphorous acids are discussed in Section 2.4.S.2. In this section only special cases of anhydride formation are described. Mixed anhydrides of amino acids and adenylic acid are produced from the corresponding acids using DCC as the condensation agent. ° Mixed anhydrides not containing amino acids, such as butyryl adenate, adenosine 5 -phosphosulfate and p-nitrophenyl-thymidine-5-phosphate are also obtained. 

Thallium triacetate, 406 Thallous carboxylates, 410 Thallous ethoxide, 407-411 Thebaine, 330, 331 Thiacyclohexane, 358 Thiazolidine-4-carboxylic acid, 27 Thiele reaction, 7-9, 12, 13 Thiepin-1,1-dioxide, 392 Thioanisole, 99, 311, 324 Thiocarbonates, 105, 106 N,N -Thiocarbonyldiimidazole, 411-412 Thiocyanogen, 105, 440 Thionyl chloride, 176, 395, 410, 412 Thiophenols, 173, 174 Thiophosgene, 412 Thiourea, 157, 412-413 Thymidine, 297, 298 Thymidine 5 -phosphate, 298 Thymine, 370 Tigonin, 136 Tin, 414... 

All the enzymes contain ferrous iron. Ferrous ions are essential for the catalytic activity of butyrobetaine hydroxylase (259), proline-4- 254) and 3- 242, 243), hydroxylases, thymidine hydroxylase 260), lysine hydroxylase 261), trimethyllysine hydroxylase 247), thymine oxygenase 262—264), cephalosporin hydroxylase 249), and hydroxy-phenylpyruvate 265—267). In addition, the enzymes show a non-stoichio-metric requirement for ascorbic acid which is supposed to maintain the ion co-factor in the ferrous oxidation state (2, 242, 243, 254). Labelling studies with butyrobetaine hydroxylase 268), proline-4-hydroxylase 269), thymine oxygenase (270), cephalosporin hydroxylase (257) and hydroxy-phenylpyruvate hydroxylase (277) all indicate a common pattern of oxygen incorporation. One atom of oxygen becomes the new hydroxyl group while the other is located in one of the carboxylic acid groups of succinic acid. 

Thymidine (9) reacts with aromatic carboxylic acids to give 5 -O-aroylthymidines (10) (eq 5). The yield of esters increases with the acidity of the carboxylic acid, indicating the importance of the protonated A -phosphonium salt (2). ... 

Materials. The following were obtained from commercial sources Swims medium S77, horse serum, and fetal calf serum (Grand Island Biologicals) MTX (Lederle Laboratories) was purified by DEAE cellulose prior to use (11) crystalline BSA, poly-L-lysine (M 35,000), hypoxanthine and thymidine (Sigma Chemical Co.) 1-etnyl-3-(3 -dimethylaminopropyl)carbodiimide hydrochloride (EDC) (Story Chemicals) folinic acid (ICN Pharmaceuticals) Blue Dextran (Pharmacia). The concentrations of the folate derivatives and MTX were determined by their respective extinction coefficients (13). MTX-BSA was synthesized according to a previously described procedure ( ) in which MTX is coupled via a terminal carboxyl group to -amino groups contained in the albumin molecule. 

The reaction of surface carboxyl groups can lead to either esters or amides. The first step in both cases is to generate acid chlorides on the diamond surface by treating it with thionyl chloride. This intermediate then can easily be reacted with the respective alcohols or amines. In this manner it has been possible, for instance, to estabhsh on a diamond film a thymidine ester that could be cormected to a strand of DNA in a subsequent Ugase-mediated reaction (Figure 6.44). Hydroxyl... 

D-arablnofuranosyl-2-cyanomethyl-lH-pyrrole-3-carboxylate,° 3-benzoyloxy-l-3-D-ribofuranosyl-pyrazole-4-carboxyllc acid, l-(2,3,5-tri-0-benzoyl-3-D-ribofuranosyl) derivatives of tetrahydro-2H-1,3-diazepine-2,4(3H)-dione and 6,7-dihydro-2H-1,3-diazepine-2(3H)-one, cis-(5R,6R)-5,6-dlhydroxy-5,6-dlhydrothymldlne (a radiation product of thymidine), " 3 -azido-3 -deoxy-thymidlne, ... 

---