Reaction #677813

ord-757d9ddc32d34083a73127f9a680b4c9

Reaction equation

CCC(C)CCCCC(=O)N[C@@H](CCN)C(=O)N[C@H](C(=O)N[C@@H](CCN)C(=O)N[C@H]1CCNC(=O)[C@H]([C@@H](C)O)NC(=O)[C@H](CCN)NC(=O)[C@H](CCN)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H](Cc2ccccc2)NC(=O)[C@@H](CCN)NC1=O)[C@@H](C)O
Polymyxin B
O=P([O-])([O-])[O-].[K+].[K+].[K+]
potassium phosphate
[Cl-].[K+]
potassium chloride
O=C(O)CN(CCN(CC(=O)O)CC(=O)O)CC(=O)O
EDTA
N[C@@H](CS)C(=O)O
cysteine
→
CC(C)C[C@@H]1NC(=O)[C@H](Cc2ccccc2)NC(=O)[C@H](CCN)NC(=O)[C@@H](NC(=O)[C@H](CCN)NC(=O)[C@@H](N)[C@@H](C)O)CCNC(=O)[C@H]([C@@H](C)O)NC(=O)[C@H](CCN)NC(=O)[C@H](CCN)NC1=O
product
CC(C)C[C@@H]1NC(=O)[C@H](Cc2ccccc2)NC(=O)[C@H](CCN)NC(=O)[C@@H](NC(=O)[C@H](CCN)NC(=O)[C@@H](N)[C@@H](C)O)CCNC(=O)[C@H]([C@@H](C)O)NC(=O)[C@H](CCN)NC(=O)[C@H](CCN)NC1=O
Polymyxin B Nonapeptide

Reactants

CCC(C)CCCCC(=O)N[C@@H](CCN)C(=O)N[C@H](C(=O)N[C@@H](CCN)C(=O)N[C@H]1CCNC(=O)[C@H]([C@@H](C)O)NC(=O)[C@H](CCN)NC(=O)[C@H](CCN)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H](Cc2ccccc2)NC(=O)[C@@H](CCN)NC1=O)[C@@H](C)O
Polymyxin B
O=P([O-])([O-])[O-].[K+].[K+].[K+]
potassium phosphate
[Cl-].[K+]
potassium chloride
O=C(O)CN(CCN(CC(=O)O)CC(=O)O)CC(=O)O
EDTA
N[C@@H](CS)C(=O)O
cysteine

Reagents

None

Solvents

CO
methanol

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    OtherThe immobilized papain was removed by filtration
  2. 2
    Concentrationthe filtrate was concentrated in vacuo
  3. 3
    Otherto leave a solid residue which
  4. 4
    workup.WAITleft at room temperature overnight
  5. 5
    OtherThe supernatant was decanted
  6. 6
    Concentrationconcentrated in vacuo
  7. 7
    OtherPolymyxin B nonapeptide was purified from the residue by SPE on C18 silica
  8. 8
    Washeluting with 0-10% aqueous methanol
  9. 9
    OtherEvaporation of the appropriate fractions

Procedure

A mixture of Polymyxin B (20 g), immobilised papain (185 ELU/g), potassium phosphate buffer (25 mM; pH 7, 1.25 L), potassium chloride (30 mM), EDTA (10 mM) and cysteine (1 mM) was incubated at 37° C. for 18 h with gentle agitation. The progress of the reaction was monitored by LC-MS using the conditions outlined in Table 1. The immobilized papain was removed by filtration and the filtrate was concentrated in vacuo to leave a solid residue which was re-suspended in 10% aqueous methanol and left at room temperature overnight. The supernatant was decanted and concentrated in vacuo. Polymyxin B nonapeptide was purified from the residue by SPE on C18 silica, eluting with 0-10% aqueous methanol. Evaporation of the appropriate fractions gave the product as a white solid. m/z 482, [M+2H]2+

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US09234006B2uspto-grants-2016_01