Phosphate → HCID 92131096, compound

Participants

Reaction Steps

A round bottom flask was charged with N2′-Deacetyl-N2′-(3-mercapto-1-oxopropyl)-maytansine (DM1, 67.9 mg, 0.092 mmol), Succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC, 32.1 mg, 0.096 mmol, 1.05 equivalents) and THF (4 mL). The solution stirred as the reagents were dissolved in the solvent to yield a clear, colorless solution. Phosphate buffer, pH 6, (4 mL, 100 mM Potassium Phosphate, 2 mM EDTA) was then added. The reaction flask was equipped with a septum and stir bar and the reaction proceeded at room temperature with vigorous stirring. The reaction appeared complete within 30 minutes as indicated by reverse-phase HPLC. Following reaction completion, the reaction volume was reduced in vacuo to give a white solid/residue. The product was isolated by silica gel chromatography, eluting with a mixture of 3% methanol in methylene chloride. Product containing fractions were combined and concentrated to dryness in vacuo to give 63 mg (63.9% yield) DM1-SMCC as a white solid. Mass spectral analysis of the isolated product gave the expected m+Na+ (m/z 1094.4) and m+Cl− (m/z 1106.2) major molecular ions (FIG. 43).

Provenance & Evidence