Trifluoroacetic acid → HCID 131714601, compound

Participants

Reaction Steps

40 g of H-Ser-Ala-OMe, TFA and 32.9 g of Boc-Leu-OH, H2O are dissolved in 400 ml of DMF. The product is cooled with an ice bath with magnetic stirring and 14.4 ml of NEM then 65.8 g of BOP and enough NEM to maintain the pH at 6.5-7 are added. The product is stirred for 2 hrs. at ambient temperature. After monitoring by TLC, the product is evaporated to dryness (0.1 mm-35°) and the oil obtained is dissolved in 1500 ml of chloroform, washed twice with a saturated NaCl solution, three times with 5% sulfate/potassium bisulfate, 3 times with saturated sodium bicarbonate, dried over Na2SO4, evaporated to dryness (30°-water-jet pump). The oil obtained is solidified in ether: Fraction A=29 g. A second jet B is obtained by addition of hexane, identical in TLC: B=13.7 g.

Provenance & Evidence