substituted naphthalamines

2-naphthalamine X 4.16 2-naphthalamine X

1-NH2,3-X NO2 2.07 2-NH2,4-X NO2 2.43
CN 2.26 CN 2.66
Cl 2.66 Cl 3.38
Br 2.67 Br 3.40
I 2.82 I 3.41
COOCH 3 3.12 COOCH 3 3.38
OCH3 3.26 OCH3 4.05
OH 3.30 1-NH2,6-X NO2 2.89
CH3 3.96 Cl 3.48
Cl 2.71 OCH3 3.90
2-NH2,5-X NO2 3.01 OH 3.97
OH 4.07 2-NH2,7-X NO2 3.10
1-NH2,5-X NO2 2.73 Cl 3.71
OH 3.96 OCH3 4.19
Cl 3.34 OH 4.25
NH2 4.21 NH2 4.66
1-NH2,7-X NO2 2.55 2-NH2,6-X NO2 2.62
Cl 3.48 OCH3 4.64
OCH3 4.07 2-NH2,8-X NO2 2.73
OH 4.20 1-NH2,4-X NO2 0.54
1-NH2,2-X NO2 -1.74 Br 3.21
1-X,2-NH2 NO2 -0.85 2-NH2,3-X NO2 1.48
1-NH2,8-X NO2 2.79,

Anilines (in 50% ethanol) 5'-IMP 8.9, 1.54, 6.04 6

Unhindered pK ref. 5-Methylcytosine 4.6, 12.4 6
Aniline 4.19 40 5-Methylcytosine deoxyriboside 5'-phosphate
p-Aminodiphenyl 3.81 40 4.4 6
2-Naphthylamine 3.77 40 3-Methyluracil 9.75 37
3-Phenanthrylamine 3.59 40
 3-Methylxanthine 8.5 (8.1), 11.3 38
m-Aminodiphenyl 3.82 40

Adenosine 3.63 6
2-Aminofluorene 4.21 40

2-Phenanthrylamine 3.60 40 " 3.3, 12.5 35

2-Anthrylamine 3.40 40 5'-AMP 3.3, 6.1 36
Hindered 3.74, 6.2-6.4 6
o-Aminodiphenyl 3.03 40 Barbituric acid 3.9, 12.5 37
Cytidine 4.11 6
peri " 4.22, 12.5 35
1-Naphthylamine 3.40 40 2'-CMP 4.3-4.4, 6.19* 6
9-Phenanthrylamine 3.19 40 5'-CMP 4.5, 6.3 6
3-Aminopyrene 2.91 40 CTP 4.6, 6.4 6
1-Phenanthrylamine 3.23 40 2,6-Diaminopurine 5.09, 10.77 6
1-Anthrylamine 3.22 40

Isoguanine 4.51, 8.99 6

Guanosine (deoxy) 1.6-2.2, 9.16-9.5 6
meso

GMP (2' + 3') 2.3, 9.36, 0.7, 5.9 6

9-Anthrylamine 2.7 40

o-Aminophenols 5'-GMP (deoxy) 2.9, 9.7, 6.4 6

3-Hydroxyanthranilic acid 10.09, 5.20 51 GTP 3.3, 9.3, 6.5 6
2-Aminophenol hydrochloride Inosine 1.2, 8.9 6
9.99, 4.86 51 " 8.75, 12.5 6
Indicators 5-Methylcytosine deoxyriboside
p-Aminoazobenzene 2.82, 2.76 60 4.5, 13.0 6
4-Chloro-2-nitroaniline -1.02, -1.03 60 1-Methyluracil 9.95 37
4,6-Dichloro-2-nitroaniline -3.61, -3.32 60 1-Methylxanthine 7.7, 12.05 38
6-Bromo-2,4-dinitroaniline -6.64, -6.71 7-Methylxanthine 8.5 (8.3) 38
2-Amino-4,5-dimethylphenol hydrochloride 10.40, 9-Methylxanthine 6.3 38
5.28 51

Purine 2.52, 8.90 37

N,N-Dimethyl-2,4-dinitroaniline -1.00, -- 60

Thymidine 9.8 6
p-Nitrodiphenylamine

-2.4 to -2.9, -2.50 60 5'-TMP 10.0, 1.6, 6.5 6

4-Methyl-2, dinitroaniline -3.96, -4.44 60 Uracil deoxyriboside 9.3 6
5'-UMP 9.5, 6.4 6
Heterocyclics UTP 9.5, 6.6 6
Nucleosides, etc. Uridine 9.25 6
Adenine 4.15, 9.80 6 " 9.17, 12.5 35
2'-AMP 3.81, 6.17 6 Xanthosine 0, 5.5, 13.0 6
3'-AMP 3.74, 5.92 6 Orotic acid 2.8, 9.45, 13 6
ADP 3.95, 6.3 36 Pyrimidine 1.30 37
ATP 4.00 (4.1), 6.5 36 Thymine 0, 9.9, 713.0 6
Barbital 7.85, 12.7 37 Uracil .5, 9.5, 13.0 6
Cytosine 4.45, 12.2 6 UMP (2' + 3') 9.43, 1.02, 5.88 6
Cytosine (deoxy) 4.25 6 UDP 9.4, 6.5 6
3' CMP 4.16-4.31, 6.04 6 Uric acid 5.4, 10.3 6
CDP 4.44 6 Xanthine 0.8, 7.44, 11.12 6
CDP, (deoxy) 4.8, 6.6 6 " 7.2 38
Guanine 3.3, 9.2, 12.3 6
Guanosine 2.2, 9.5 6
" 1.6, 9.16, 12.5 35
5'-GMP 2.4, 9.4, 6.1 6
GDP 2.9, 9.6, 6.3 6
Hypoxanthine 1.98, 8.94, 12.10 6
Heterocyclic Bases (Ref. 2)

5 4
63

72N
N
8 NN
Pyridine 5.14* Isoquinoline 5.14* Benzoquinoline 5.05*
pK (20°) Quinoline 4.85*
 N

6 5
4
73

82

9 N10 1 NN

Acridine 5.60 5,6-Benzoquinoline 7,8-Benzoquinoline Phenanthridine 3.30a

5.15* 4.25*

N N

2,3-Benzacridine 4.52a 3,4-Benzacridine 4.70* a

1,2-Benzacridine 3.45
N
NN
N N N
Pyridazine 2.10* Pyrimidine 1.10* Pyrazine 0.37*

N N
N
N NN N
N
Cinnoline 2.64* Phthalazine 3.39* Quinazoline
3.31*Quinoxaline 0.6*
a
50% EtOH

Heterocyclics 3-Hydroxy 8.81, 5.52 39

Aureomycin 3.30, 7.44, 9.27 77 5-Hydroxy (acridone) --f, -0.32 39
Iridine --, 5.62 39 5-Methoxy --, 7 39
Acridine 1-- 2-- 3-- 4-- 5-- 9-- Ref. 2
H-- 5.60* 4.11a
H2N-- 4.40* 8.04* 5.88* 6.04* 9.99*
 3.59a 7.61a 5.03a 5.50a 9.45a
HO-- 4.18a 4.86a 5.5239 4.45a -.3239
10.7a 9.9a 8.8139 9.4* >12
CH 3-- 3.95a 4.60a 4.70a
H2K-(1-CH 3--)-- 4.79a 9.73s 3.22a
1,9-(CH 3)2-- 2.88a
a 50% ethanol; ref. 39

8-amino-1,2-benzacridine 6.72 40 α,α'-dipyridyl 4.43 6

2-amino-4-methyl-5,6-benzoquinoline 7.14 4-amino- 8.75a 19
40 4-amino-2-methyl- 9.45a 19
3-amino-6,7-benzoquinoline 4.78 40 4-amino-2-methyl-8-chloro- 5.95a 19
8-amino-3,4-benzacridine 7.42 40 8-chloro- 2.5a 19
1'-amino-5,6-benzoquinoline 5.03 40 3,4-diamino- 8.15a 19
4'-amino-5,6-benzoquinoline 5.20 40 a

2-amino-4-methyl-7,8,benzoquinoline 3-amino- 4.78, 3.73a 19

6.74 40 7,8-benzquinoline 4.25, 3.15 19
6,7-benzoquinoline 5.05, 3.84a 19 4-amino- 7.68a 19
5,6-benzoquinoline 5.15, 3.90a 19 4-amino-2-methyl- 7.96a 19
4-amino- 7.99a 19 2-amino-4-methyl- 6.74, 6.02a 19
2-methyl- 4.44a 19 6-amino-2-methyl- 5.23a 19
4-amino-2-methyl- 8.45a 19 1'-amino-2-methyl- 4.75a 19
2-amino-4-methyl- 7.14, 6.51a 19 3,4-benzacridine 4.70, 4.16a 19
4'-amino- 5.20, 4.10a 19 5-amino 8.41a 19
3'-amino- 4.02a 19 7-amino- 5.03a 19
1'-amino- 5.03 19 8-amino- 7.42 (6.51)a 19
2',4'-diamino- 4.91a 19 8-acetamido- 4.48a 19
Benziminazole 5.53 19 8-dimethylamino- 7.31, 6.99 19
2-amino- 7.54 19 1,2-benzacridine 3.45a 19
Benztriazole 1.6 19 5-amino- 8.13a 19
Benzthiazole 1.2, 0.1a 19 7-amino 4.05a 19
2-amino- 4.51 19 8-amino- 6.72, 5.97a 19
benzoxazole (decomp.) 19 4',5-diamino- 8.44a 19

2-amino- 3.73 Cinnoline19 --, 0.21 39

2,3-benzacridine 4.52a 3-hydroxy
19 8.64, 0.21 39
5-amino- 9.72a 5-hydroxy
19 7.40, 1.92 39
5-acetamido- 4.56a 7-hydroxy
19 7.56, 3.31 39
7-amino- 5.38a 4-methoxy
19 Heterocyclics --, 3.21 39
5-amino-6:7:8:9-tetrahydro- 9.66a 19
Caffeine 0.61 4
cinchonine 7.2 o,o'-dipyridyl
4 4.43 6
Cinnoline 2.70 hydantoin19 9.16 42
4-amino- 6.84 5-isopropyl-2-thio-
19 8.70 42
Cocaine 7.6 5,5-pentamethylene2-thio
4 8.79 42
Cinnoline 4-hydroxy 3,5,5-trimethyl-2-thio
9.27, 0.35 39 10.80 42
6-hydroxy 3-methyl-5,5-pentamethylene-2-thio-
7.52, 3.65 39
-hydroxy 8.20, 2.74 39 11.23 42
Imidazoles
1-Hydroxy- 11.00, -2 39
Picolimic acid 5.52 4
5,5-dimethyl-2-thio- 8.71 42
5,5-Diphenyl-2-thio- 7.69 42
1-Methyl-5,5-pentamethyl-ene-2-thio-
9.25 42
4-Methyl- 7.45 43
Imidazole 6.95 43
4-(2',4'-Dihydroxyphenyl)- 6.45 43
Carbobenzoxy-L-histidyl-L-tyrosine ethyl
ester 6.25 43
6-Aminobenz- 6.0 (NH2 3.0)
Benzimidazole 5.4 43

2-Methylimidazole 7.75 43 Histidin

N-Acetylhistidine 7.05 43
2-Methyl-4-hydroxy-aminobenz- 6.65 43
4-Hydroxymethyl- 6.45 43 2-Methy
2-Methylbenz- 6.1 43
Histamine 6.0 43 4-Hydro
4-Hydroxy-6-aminobenz- 5.9 43 b2-Hyd

4-Hydroxybenz- 5.3 (OH 9.5)43

4-Methoxybenz- 5.1 43 b2-Hyd

4-Bromo- 3.7 43
6-Nitrobenz- 3.05, 10.6 43 4-Hydro
4-Nitro- 1.5, 9.1 43 1-Amin
isoQuinolines 4-Amin
1-Hydroxy- -1.2 44 6-Amin
5-Hydroxy 5.40, 8.45 44 8-Amin
3-Amino- 5.05 40 7-Hydro
5-Amino- 5.59 40 1-Metho
Amino- 6.20 40 4-NO2
6-Hydroxy- 5.85, 9.15 44 4-Br
8-Hydroxy- 5.66, 8.40 44 1-Hydro
2-Methylisoquinolone -1.8 44 5-Methy
Isoquinoline 5.46, 5.14 44, 19 Phenant
Phenazine --, 1.23 39 1-Amin
2-Hydroxy- 7.5, 2.6 39 2,2'-Dip
10-Methyl-2-phenazone --, 3.0 2-Hydro
6-Aminophenanthridine 9- 6.88 40 7-Hydro
Aminophenanthridine o- 7.31 40 9-Metho
Phenanthroline p- 4.27a, 5.2 19 methyl2
Phenanthroline 3.12a 19 methyl6
1,10-Diamino-3,8-Dimethyl- 8.78a, 6.31a
Phenazi
Phenanthridine --, 4.65 44
1-Amin
6-Hydroxy- 8.43, 5.35 44
2-Amin
9-Hydroxy (phenanthridone) <-1.5 44
1,3-Dia
9-Amino- 7.31, 6.75a 19 2,3-Dia
2,7,9-Triamino- 8.06a 19 2,7-Dia
Phthalazine 3.47 19 1-Amino- 6.60 19 acid
Pyridines
2-Amino- 6.86 41
4-Amino- 9.17 41
2-Methyl- 5.94b 45
2-Vinyl- 4.98 45
2-Chloro- 0.49 45
2,4,6-Trihydroxy- 4,6, 9.0, 13 39
1-Methyl-4-pyridone 3.33
2-(N-Methylacetamido)- 2.01 46
2-Benzamido- 3.33
2-(N-Methylbenzamido)- 1.44
3-(N-Methylacetamod)- 3.52 46
3-(N-Methylbenzamido)- 3.66 46
4-(N-Methylacetamido)- 4.62 46

4-(N-Methylbenzamido)- 4.68 46 (CH

3)2CH- 5.83b 5.72b 6.02b
4-Benzamido- 5.32 46
CH 3CO 3.18b
3-NO2 0.81 88 H2N-
6.68b 5.80b 8.96b
3-COO–
4.77 47
CONH247 3.40 3.61

2,3-Me2 6.60 48 NC-

47 1.45
2,5-Me2 6.47 48
3,4-Me2 6.52 48
2,4,6-Me3 7.48 48
4-OEt 6.67 48
3-Cl 2.84 48
3-CO2Et 3.35 48
3-COOH 3.13 88

2-Amyl- 6.00b 45

2-Hexyl- 5.95b 45

2-Benzyl- 5.13 45
2-Bromo- 0.71 45
2,4-Dihydroxy 6.50, 13, 1.37 39
1-Methyl-2-pyridone 0.32 39
2-Acetamido- 4.09 46
1-Methylpyrid-2-one acetylimine 7.12 46
3-Acetamido- 4.46 46
3-Benzamido- 3.80 46
1-Methylpyrid-4-one acetylimine
11.03 46
1-Methylpyrid-4-one benzylimine 9.89 46
4-COO– 4.90 47
2,4-Me2 6.72 48
2,6-Me2 6.77 48
3,5-Me2 6.14 48
2-Me,5-Et 6.51 48
3-F 3.10 48
3-Br 2.84 48
4-CO2Et 3.45 48
Pyridine N-oxides (see oxygen acids)
Substituted Pyridines
Pyridine 2- 3- 4-
H- 5.17b
Cl- 0.72b 2.84b
I- 1.82b 3.25b
CH 3CH 2- 5.97b 5.70b 6.02b
(CH 3)3C- 5.76b 5.82b 5.99b
HO- 0.75 4.86 3.27
11.62 8.72 11.09
SO3-47 2.9
CH 3O- 3.28 4.88 6.62
F- -0.44b 2.97b
Br- 0.90b 2.84b
CH 3- 5.97b 5.68b 6.02b

Ortho-Substituted Pyridines (in 50%

ethanol)Pyridazine 2.33 19
Substituent pK ref. 3-
Hydroxy-10.46, -1.8 39
H- 4.38 2
3,6-Dihydroxy- 5,67, -2.2, 13 39
2-C2H5- 4.93 2 4-
Methoxy- 3.70 39
2-(CH 3) 4.68 2 3-
Amino- 5.19 19
2,6-[(CH
3)2CH]2 3.58 2 4-
Hydroxy-8.68, 1.07 39
2-(CH 3)3C-4.68 2 3-
Methoxy- 2.52 39
2-C2H5-6-(CH 3)3C-
4.36 2 3,6-
Dimethoxy- 1.61 39

2,6-[(CH 3)3C]2– 3.58 2 For

complex chelating agents, see also ref. 77
2-CH 3- 5.052 b thermodynamic at
25°.
2-(CH 3)2CH- 4.82 2
2,6-(CH 3)2 5.77 2
2,6-[(CH 3)3C]2 3.58 2
2-CH 3-6-(CH 3)3C 5.52 2
2-(CH 3)2CH-6-(CH3)3C- 5.13 2
pKN H 35° pKOH
Benzimidazole6.00 5.58 5.36
2-Methyl 6.96 6.29 6.18
---
2-Ethyl 6.90 6.27 6.14 --
2-Hydroxymethyl ---
5.40 --- 11.55 ref. 86
1-Methyl-2-hydroxymethyl --- 5.55
--- 11.45
2,4-Dihydroxy-(Uracil) 9.38,
12 39
4,6-Dihydroxy- 5.4 39
2,4,6-Trihydroxy-(Barbituric acid)
Other (ref.
95) 3.9,
12.5 39
Thiazolidine6.31 2-Methoxy-
<1 39
Methyl thiazolidine-4-carboxylate 4.00 4-
Methoxy- 2.5 39
Thiazolidine-4-COOH 1.51, 6.21 1-
Methyl-2-pyrimidone 2.50 39
3-Methyl-4-pyrimidone 1.84 39
(ref. 96)4-Amino- 5.71 19

2-Methyl-∆2-oxazoline 5.5 2-
Amino-4-methyl-4.15 19

4-Carbamoyl-2-phenyl-∆2-oxazoline 2.9 2,4-

Diamino- 7.26 19

2-Phenyl-∆2-oxazoline 4.4 4-
Methyl- 1.98 19
4-Hydroxy- 8.59,
1.85 39