(2,5-dioxopyrrolidin-1-yl) 2-(2,5-dioxopyrrol-1-yl)acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Maleimidoacetic acid (155 mg, 1.0 mmol) in 5 ml of diglyme was treated at 0° C. with N-hydroxysuccinimide (127 mg, 1.1 mmol) and dicyclohexylcarbodiimide (227 mg, 1.1 mmol). After 1 hour at 0° C. and 3 hours at room temperature, the reaction mixture was filtered and evaporated to dryness to yield 0.25 g of crude maleimidoacetic acid N-succinimidyl ester. 3 hours at room temperature, the reaction mixture was filtered evaporated to dryness

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Maleimidoacetic acid (155 mg, 1.0 mmol) in 5 ml of diglyme was treated at 0° C. with N-hydroxysuccinimide (127 mg, 1.1 mmol) and dicyclohexylcarbodiimide (227 mg, 1.1 mmol). After 1 hour at 0° C. and 3 hours at room temperature, the reaction mixture was filtered and evaporated to dryness to yield 0.25 g of crude maleimidoacetic acid N-succinimidyl ester. 3 hours at room temperature, the reaction mixture was filtered evaporated to dryness

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Maleimidoacetic acid (155 mg, 1.0 mmol) in 5 ml of diglyme was treated at 0° C. with N-hydroxysuccinimide (127 mg, 1.1 mmol) and dicyclohexylcarbodiimide (227 mg, 1.1 mmol). After 1 hour at 0° C. and 3 hours at room temperature, the reaction mixture was filtered and evaporated to dryness to yield 0.25 g of crude maleimidoacetic acid N-succinimidyl ester. 3 hours at room temperature, the reaction mixture was filtered evaporated to dryness