Reexamining Povarov Reaction’s Scope and Limitation in the Generation of HCV-NS4A Peptidomimetics
Table 3
THQ and THN derivatives preparation.
Entry
Product no.
Amine
Aldehyde
Alkene
Catalyst
Product %
29
5a
1b
PhCHO (2a)
DHP (3b)
CAN
43% 8% (isolated)
30
M-KSF
ND
31
5b
1b
EtGlx (2d)
BVE (3d)
CAN
32%
32
M-KSF
25%
33
5c
1b
Furfural (2c)
DHF (3c)
CAN
23%
34
M-KSF
17%
35
5d
1c
PhCHO (2a)
DHP (3b)
CAN
ND
36
M-KSF
ND
37
CAN (10x)§
ND
38
M-KSF (10x)§
ND
39
5e
1c
Furfural (2c)
DHP (3b)
CAN
ND
40
5f
1c
1-Butanal (2b)
EVE (3a)
CAN
29% 7% (isolated)
41
CAN (10x)§
ND
42
M-KSF (10x)§
ND
43
5g
1c
Furfural (2c)
BVE (3d)
CAN
33% 8% (isolated)
44
5h
1c
Furfural (2c)
DHF (3c)
CAN
17%
45
5i
1c
4-MeHexCHO (2f)
BVE (3d)
CAN (10x)§
22%
46
CAN
30%
47
5j
1c
4-MeHexCHO (2f)
DHF (3c)
M-KSF
3%
48
5k
1c
PyrCHO (2g)
DHF (3c)
CAN
64%
49
M-KSF
ND
50
5l
1c
PyrCHO (2g)
DHP (3b)
CAN
67% 32% (isolated)
51
M-KSF
ND
52
5m
1c
PyrCHO (2g)
BVE (3d)
CAN
58%
53
M-KSF
ND
PhCHO = Benzaldehyde; EGlx = Ethyl glyoxylate; 4-MeHexCHO = (S)-4-methylhexanal; PyrCHO = 2-pyridinecarbaldehyde; EVE = Ethyl vinyl ether; DHP = 3,4-Dihyro-2H-pyran; DHF = 2,3-Dihydrofuran; BVE = Benzyl vinyl ether. Product percentages shown are for LCMS analysis in crude mixture unless mentioned between parentheses. §The catalyst was used in 10-fold amount larger than what was mentioned in the section Experiment.