Dicyclohexylcarbodiimide → N,N'-Dicyclohexylurea

HRID 846856Notes

Reaction equation

HRID 846856 reaction equation
C1C=CC2N([OH:10])N=NC=2C=1.[CH2:11]1[CH2:16][CH2:15][CH:14]([N:17]=[C:18]=[N:19][CH:20]2[CH2:25][CH2:24][CH2:23][CH2:22][CH2:21]2)[CH2:13][CH2:12]1>CN(C=O)C.C(OCC)(=O)C>[CH:20]1([NH:19][C:18]([NH:17][CH:14]2[CH2:13][CH2:12][CH2:11][CH2:16][CH2:15]2)=[O:10])[CH2:25][CH2:24][CH2:23][CH2:22][CH2:21]1

Participants

5

Reactant 2

HCID 10868DicyclohexylcarbodiimideHCID 757711-Hydroxybenzotriazole

Product 1

HCID 4277N,N'-Dicyclohexylurea

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Procedure

ε-N-2ClZ-L-lysyl-L-aspartyl-β-benzyl ester-L-valyl-L-tyrosyl-O-benzyl ether-benzyl ester-3-thioamide (2 mmol) was dissolved in dry DMF (0.5 ml) at 0° C. under N2 and α-N-Boc-N-tosyl-L-arginine (2 mmol) was added to the solution with stirring. HOBt (2 mmol) and DCC (2 mmol) were added slowly at 0° C. and stirring was allowed to continue overnight. The mixture was diluted with 8 volumes of ethyl acetate and the N,N'-dicyclohexylurea so formed was filtered away from the solution. The filtrate was transferred to a separating funnel and washed successively with 5% aqueous sodium bicarbonate, 5% aqueous citric acid, and saturated brine. The organic phase was collected and dried over MgSO4, filtered, and concentrated in vacuo. The residue was purification by flash chromotography using 9:1 chloroform-methanol as an eluant to afford the α-N-Boc-N-tosyl-L-arginyl-ε-N-2ClZ-L-lysyl-L-aspartyl-β-benzyl ester-L-valyl-L-tyrosyl-O-benzyl ether-benzyl ester-4-thioamide in good yield (78%). The following physical characteristics were recorded for the compound: Melting point 105°-107° C.; IR (CHCl3) 1756, 1%90 cm-1UV (CHCl3) lambdamax 271. Elemental composition (C71H84Cl3N9O14S2): Theoretical: C, 58.13; H, 5.65; N, 8.34; S, 4.79. Found: C, 58.54; H, 5.81; N, 8.65; S, 4.40.

Workup

  1. stirringstirring

Sources & evidence

ORD record
ord-7dce9129926f455b9b8a0fdaa418ca94
Source dataset
uspto-grants-1992_08
Patent number
US05138061

Reaction notes

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