Table 1 Optimization of the reaction conditionsa

From: Development of ketalized unsaturated saccharides as multifunctional cysteine-targeting covalent warheads

View full size image

 

Acid (Equiv)

Solvent

Temp (°C)

Time (h)

Yield (%)b

1

TfOH(1)

DCM

Rtc

2 h

16%

2

TFA (1)

DCM

Rt

2 h

n.p.d

3

MeSO3H (1)

DCM

Rt

2 h

n.p.

4

HCl (1)

DCM

Rt

2 h

n.p.

5

TfOH(2)

DCM

Rt

2 h

32%

6

TfOH(3)

DCM

Rt

2 h

40%

7

TfOH(4)

DCM

Rt

2 h

27%

8

TfOH(3)

DCM

40

2 h

60%

9

TfOH(3)

DCE

60

2 h

42%

10

TfOH(3)

THF

40

2 h

n.p.

11

TfOH(3)

Et2O

40

2 h

n.p.

12

TfOH(3)

toluene

40

2 h

n.p.

  1. a0.5 mmol of Compound 1 and different acids were mixed in the solvents for 30 min, then Compound 2 was added and reacted under the protection of nitrogen for 2 h.
  2. bHPLC yield.
  3. cRoom temperature.
  4. dNo product.
Back to article page