Nucleosides. XXXIII. N⁴-Acylated 5-Fluorocytosines and a Direct Synthesis of 5-Fluoro-2'-deoxycytidine¹

Abstract

Duschinsky, Gabriel, 11 offer, Berger, Tits worth, Gkunbehg, Bvrchenal, and Fox Aoi.!) K.j(J()a (8.85 g, 04.0 mmoles), and dimotliyliormamide (20 mli was heated to 115°, and l,2-dibromoethane (3.00 g, 16.0 mmoles) was added dropwise. The resultant mixture was heated at 115-120°for 5 hr, allowed to cool somewhat, and [inured into water (100 ml). The precipitate that formed was collected, washed with water, and dried in mato, lieerystallization of this material (0.91 g, mp 132 -134°) from ethanol gave 0.67 g (17f,' ) of VII as white needles, mp 144-146°. B. From 2-Aminoethanol.solution of p-tolueiicsulfonyl chloride (860 g, 4.52 moles) in dimethylformamide (800 ml) was added from a dropping funnel to a mechanically stirred mixture of 2-aminoethanol (276 g, 4.52 moles), anhydrous KSC(>3 (624 g, 4.52 moles), and dimethylformamide (1.0 ].). Throughout the addition period the temperature of the reaction mixture was maintained at 30-35°, moderate external cooling being necessary. Fifteen minutes after the addition had been completed, the continuously' stirred mixture was gradually heated to 1 15-120°. More K2CO3 (1.26 kg, 9.03 moles) was added followed by the dropwise addition during about 45 min of 1,2-dibromocthane (424 g, 2.26 moles). The resultant mixture was stirred and heated at 115 -120°for 5 hr, allowed to cool, and poured into water (25 L). The aqueous mixture was allowed to stand overnight at room temperature, and the white crystalline precipitate that separated was collected and washed thoroughly with water. The product, dried in vacua (1VU), was obtained in 15% crude yield (81.0 g) and melted at 139 -141°. ltccrysiallization from ethanol raised the melting point to 144-146°. Further recrystallizatiou from benzene-ligroin (bp 30-60°) gave a sample of VII with mp 146-147°. ('. From Morpholine. A freshly prepared solution of µtoluenesulfonyl chloride (2.86 g, .15.0 mmoles) in dimcihylformamide (5 ml) was added dropwise t.u a magnetically stirred solution of morpholine (2.61 g, 30.0 mmoles) in the same solvent :5 ml) at such a rale that the reaction temperature did not exceed 40°. The mix!lire was stirred 1 hr longer at room temperature and was then diluted with water (80 nil). The white prceipilate that formed was collected, washed with water, and dried in I'acaa at mom temperature [yield 2.74 g (76%,), mp 144 145% Recrystallizatiou from benzene-ligroin raised the melting ¡mint to 147-148°(lit.13 nip 1-17% Melting points of mixtures of this authentic All with the products described above ( and lit were not depressed, and their infrared speeira were identical. Detosylation of VII. When Vf] (1-1.1 g) [erroneously identified at the I ¡me as III (n -2) on the basis of melting point [ was subjected to treatment with boiling 48% HBr (150 ml initially) in ihe manner de-a-ribed above for conversion of III uto IV in -3 6), the only product isolated was morpholine hydrobromide (1.21 g, 12% yield), mp 210-212°( recrystallized from etlmnol'i. No effort• was made In isolate any products l hat might have resulted from eth...

Anticandidal activity of 5-fluorocytosine-peptide conjugates

“…The oily residue was then crystallized (5.7 g, 58%) from ethyl acetate-hexane, mp 91-93 °C. The anhydride product 14 which was homogeneous on silica thin layers (ethyl acetate) showed an Rf different from 18 and gave the expected IR bands: NMR (CDC13) 1.44 (9 H, s, 3 CH3), 1.56-2.72 (4 H, complex, CH2C=0 and CH2), 4.24-4.64 (1 H, m, -CH), 5.30 (2 H, s, benzyl), 5.30-5.48…”

“…!V4-y-(feri-Butoxycarbonyl-L-glutamyl-a-benzyl ester)-5-fluorocytosine (18). Procedure A. fert-Butoxycarbonyl-L-glutamic acid -benzyl ester (19; 9.8 g, 0.029 mol) and 5fluorocytosine (2.5 g, 0.019 mol) was suspended in anhydrous dimethylformamide (150 mL) at 40 °C.…”

“…Acid chlorides in pyridine or anhydrides of low-molecular-weight aliphatic and aromatic carboxylic acids, at reaction temperatures of >100 °C, have been used to prepare mono-N4-acylated 5-fluorocytosines. 18 We did not succeed in preparing 11 (Scheme I) by reacting 5-FC with the acid chloride of /3-carboxypropionyl-Gly-GIy-OBz in pyridine at 100 °C. As an alternative approach, we unsuccessfully sought to prepare iV4-(j3-carboxypropionyl)-5-fIuorocytosine by reacting 5-FC with succinic anhydride.…”

Cancer Chemotherapy with Purine and Pyrimidine Analogues

“…2) was synthesized by Wempen et al (219), and found by Burchenal et al (220) to be as active as FUdR against some mouse leukemias, and FCdR is rapidly deaminated to FUdR (178). Duschinsky et al (221) demonstrated that the N -p-toluyl-FCdR is very active against some mouse leukemias, AraFC was made by Fox et al (222), and found by Burchenal et al (223) to be very active against some mouse leukemias. 5 -Trifluoromethyl-2' -deoxyuridine (" trifluorothymidine," F3 T dR).-This compound (XVIII, Fig.…”