反应详情

7.7 ml (60mmol) of N-ethylmorpholine, 4.5 g (33mmol) of 1-hydroxy-1H-benzotriazole and 12.8 g (30 mmol) of N-cyclohexyl-N'-(2-morpholinoethyl)-carbodiimide methyl-p-toluenesulfonate (CMC) were added, in analogy with Examples 90b) and c), to 5.7 g (30 mmol) of 4-chloro-3-methoxypyridine-2-carboxylic acid and 14.2 g (30mmol) of glycine hexadecyl ester tosylate (m.p. approximately 90° C., prepared from glycine, 1-hexadecanol and p-toluene-sulfonic acid on a water separator using toluene) in 300 ml of dichloromethane, and the mixture was stirred for 24 h. The undissolved material was then filtered off with suction and the filtrate was extracted by shaking with an aqueous solution of Na bicarbonate, with water and with aqueous hydrochloric acids the organic phase was concentrated and the residue (14 g) was dissolved in 500 ml of tetrahydrofuran/methanol (1:1), and after that Pd/C (10%) was added to this mixture, which was hydrogenated using a hydrogenation vessel. Once the uptake of hydrogen was complete, the catalyst was filtered off with suction and the filtrate was concentrated and the residue chromatographed on silica gel using ethyl acetate. Appropriate fractions were concentrated and the residue was crystallized using diisopropyl ether. 2.1 g of the title compound were obtained as a colorless substance, m.p. 63°-65° C.

1. filtrationThe undissolved material was then filtered off with suction
2. extractionthe filtrate was extracted
3. stirringby shaking with an aqueous solution of Na bicarbonate, with water and with aqueous hydrochloric acids the organic phase
4. concentrationwas concentrated
5. dissolutionthe residue (14 g) was dissolved in 500 ml of tetrahydrofuran/methanol (1:1)
6. additionafter that Pd/C (10%) was added to this mixture, which
7. filtrationthe catalyst was filtered off with suction
8. concentrationthe filtrate was concentrated
9. customthe residue chromatographed on silica gel
10. concentrationAppropriate fractions were concentrated
11. customthe residue was crystallized