Le sildénafil présent dans Kamagra exerce une inhibition réversible de la PDE5, modulant la cascade GMPc et favorisant une vasodilatation localisée. L’absorption digestive varie selon la forme utilisée, comprimés classiques ou gels oraux. La distribution tissulaire est large et la liaison protéique élevée, avoisinant 96 %. La métabolisation hépatique génère un métabolite actif contribuant à l’effet pharmacologique global. La demi-vie reste courte, avec disparition plasmatique en quelques heures. Les interactions significatives concernent surtout les nitrés organiques et inhibiteurs puissants du CYP3A4. Dans les publications techniques, kamagra en ligne est souvent cité dans le cadre d’analyses comparatives portant sur les différences de formulations et de cinétique d’absorption.

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pKa Values
For complex chelating agents, see also reference 77.
Note. This document was compiled by W.P. Jencks and has been added to by F.H. Westheimer Compound
* Indicates a thermodynamic value. PHOSPHATES AND PHOSPHONATES
Phosphates
Compound
Arylphosphonic acids
Phosphonates
H2O3PCH2CH(CH3)PO3H2 <2, 2.6, 7.00, 9.27 57 **These values were obtained in 50% ethanol.
(a) The compounds were not sufficiently soluble.
For graphical plots of a large number of substituted Acetic acids, substituted
Phosphonates (Ref. 2)
-NH3+ -NH3+
Phosphines in acetonitrile, see ref. 89.
CARBOXYLIC ACIDS
Aliphatic
Compound
Unsaturated acids (25°)
Compound
Compound
Unsaturated acids, Cis- and Trans-
Dicarboxylic acids, unsaturated*
Maleic
Alicyclic Dicarboxylic acids
Itaconic (1-Propene-2-3-dicarboxylic acid) Aliphatic
Alicyclic Dicarboxylic acids
Compound
Compound
Dicarboxylic acids*
oxalic
Aliphatic
Bicyclo[2.2.2]octane-1-carboxylic acids, 4-
substituted
Lysergic acid, etc.
Hydroxycyclohexanecarboxylic acids
Aromatic
Substituted benzoic acids (ref. 2)
*thermodynamicfor complex chelating agents, see also ref. 84.
Benzoic acid
see also page 9a for more carboxylic acids.
Ortho-substituted benzoic acids
Benzoic acid
Benzene Polycarboxylic acids
Position of carboxyl pKI
Carboxylic Acids
N-2-sulfoethyliminodiacetic 1.92, 2.28, 8.16 Di-(carboxymethyl)-aminomethyl phosphonic Compound
Compound
4,5-dihydroxybenzene-1,3 disulphonic acid 7.66 ALCOHOLS and other OXYGEN ACIDS
Alcohols
Compound
Compound
Triphenylmethanols in H2SO4 HC1O4 HNO3 ref
Unsubstituted triphenyl-
Substituent effects for ionization of RCH2OH
Hydroxamic acids
Other oxygen acids
OTHER OXYGEN ACIDS
Hydroxamic acids
Aceto-
Compound
Pyridine oxides
5-Methyl-1,2,3-cyclohexanetrione-1,3-dioxime 5-Methyl-1,2,3-cyclohexane-trionetrioxime 2-Methylamino-1-methoxypyridinium toluene-p-sulphonate Oxygen acids
sulfinic acids
Pyridine 1-oxides
Peroxyacids
Peroxides ROOH (Ref. 70)
H
2-Pyrrolidoone-5-carboxylic acid (glucamicacid) Hydroxamic acids
Amino Acids
Compound
Peptides
Compound
-NH2 Ref.
Compound
NITROGEN COMPOUNDS
Aliphatic Amines pK
X(CH2)2NH3
X(CH2)3NH3
X(CH2)4NH3
X(CH2)5NH3
Secondary amines
Aliphatic Amines
Secondary Amines
Tertiary amines
1-Diethylamino-hexane-thiol-(6)
Cyanoamines
Phenylethylamines
For complex chelating agents of aliphatic amines, N-methyl-2-(3,4-dihydroxyphenyl)-ethylamine Fluoro-substituted amines
Ring amines and imines (in 80% methyl cellosolve) (ref. 2)
Pentamethylene
Amines other
Anilines
Monosubstituted
Substituent
Dimethyl
H
Dimethyl (in 50% ethanol)
Substituent XC6H4N(CH3)2
Ortho-substituted anilines (in 50% ethanol)
Substituted Naphthylamines
N-substituted anilines*
C6H5N(CH3)R C6H5NR2 2-CH3C6H4NHR
2-CH3C6H4NR2
Secondary amines
N-Butylaminoacetic acid
Primary amines
N,N'-di-n-propylethylenediamine 8.14, 10.97 Ethylenediamine-N,N'-diacetic acid 6.42, 9.46 1,3-diamino-2,2-dimethylpropane 8.18, 10.22 Ethylenediamine-N,N-diacetic acid 5.58, 11.05Furfurylamine Tertiary amines
2-(2-hydroxypropylamino)-ethylamine 6.94, Methyl-α-amino-β-mercaptoproionate 6.56, N-2-hydroxyethyliminodiacetic acid 2.2, 8.73 ANILINES (Ref. 88)
m-Substituted anilines
NAPHTHALAMINES
substituted naphthalamines
2-naphthalamine
2-naphthalamine
Anilines (in 50% ethanol)
Unhindered
5-Methylcytosine deoxyriboside 5'-phosphate Hindered
o-Aminophenols
Indicators
N,N-Dimethyl-2,4-dinitroaniline -1.00, -- Heterocyclics
Nucleosides, etc.
Heterocyclics
Acridine
a 50% ethanol; ref. 398-amino-1,2-benzacridine Heterocyclics
hydantoin
Imidazoles
isoQuinolines
Pyridines
Carbobenzoxy-L-histidyl-L-tyrosine ethylester 1-Methylpyrid-4-one benzylimine 9.89 464-COO– Pyridine N-oxides (see oxygen acids) Substituted Pyridines
Pyridine
Ortho-Substituted Pyridines (in 50% ethanol)
Substituent
For complex chelating agents, see also ref. 77 Heterocyclics
Pyrazines
Miscellaneous
Quinoline
Quinoline
Quinazoline
SPECIAL NITROGEN COMPOUNDS
Hydroxylamines
Hydroxylamine
Heterocyclics
Quinoxaline
Hydrazines (30°)
Nitrogen compounds, miscellaneous
Other
S-Methylisothiourea
Hydrazones Hydrazone of:
Cinchona Alkaloids (in 80% aqueous methyl
Semicarbazones of:
Amidoximes
Ox-
Mercaptans, RSH
R
CH3CCH2-
CARBON ACIDS
Bis-( -Diketones):[(RCO)(R'CO)CH]2CHR (in 50% dioxane)
Bis-( -Diketones) (RCO)-(R'CO)CH-Y-CH(COR)(COR') (in 50% dioxane)
Bis-( -Diketones) RCOCH2CO-Y-COCH2COR (in 75% dioxane)
Indicators
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