成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List BOC-MET-ENKEPHALIN
59481-77-5

BOC-MET-ENKEPHALIN synthesis

10synthesis methods
-

Yield:59481-77-5 685 mg (68.7%)

Reaction Conditions:

with triethanolamine in diethyl ether;ethanol;water;acetonitrile;

Steps:

26 Production of Boc-Tyr-Gly-Gly-Phe-Met-OH

EXAMPLE 26 Production of Boc-Tyr-Gly-Gly-Phe-Met-OH In 5 ml of 50% aqueous acetonitrile were dissolved 900 mg of H-Tyr-Gly-Gly-Phe-Met-OH. To the solution was added 0.52 ml of TEA. The mixture was cooled with ice, to which were added 720 mg of Boc-SDP, followed by stirring for 15 hours. The solvent was distilled off. The residue was dissolved in 10 ml of water, and the solution was washed with AcOEt. The aqueous layer was concentrated. To the residue were added 2 ml each of acetic acid and 80% EtOH. The mixtue was placed on a column (3*48 cm) of Sephadex LH-20. Elution was conducted with 80% EtOH, and fractions of 200 to 235 ml were collected and concentrated. The concentrate was dissolved in 30 ml of water and the solution was acidified with AcOH, which was then subjected to extraction with AcOEt. The extract was washed with water and dried over anhydrous sodium sulfate. The solvent was distilled off, and to the residue was added diethyl ether. The resulting powdery product was recovered by filtration and recrystallized from AcOEt. Yield 685 mg (68.7%); m.p. 159°-160° C. (decomp.); [α]D24 -16.8° (c=0.94, DMF); Rf1 =0.21, Rf2 =0.68, Rf3 =0.41. Elemental analysis, for C32 H43 O9 N5 S: Calcd.: C, 57.04; H, 6.43; N, 10.40; S, 4.76; Found: C, 56.58; H, 6.47; N, 10.25; S, 4.76

References:

US4358440,1982,A

BOC-MET-ENKEPHALIN Related Search: