- Determination of critical micellar concentration of homologous 2-alkoxyphenylcarbamoyloxyethyl-morpholinium chlorides
-
The critical micellar concentrations of selected alkyloxy homologues of local anesthetic 4-(2-[(2-alkoxyphenyl)carbamoyl]oxy ethyl)morpholin-4-ium chloride with nc = 2, 4, 5, 6, 7, 8, and 9 carbons in alkyloxy tail were determined by absorption spectroscopy in the UV–vis spectral region with the use of a pyrene probe. Within the homologous series of the studied amphiphilic compounds, the ln(cmc) was observed to be dependent linearly on the number of carbon atoms nc in the hydrophobic tail: ln(cmc) = 0.705–0.966 nc. The Gibbs free energy, necessary for the transfer of the methylene group of the alkoxy chain from the water phase into the inner part of the micelle at the temperature of 25?C and pH ≈ 4.5–5.0, was found to be ?2.39 kJ/mol. The experimentally determined cmc values showed good correlations with the predicted values of the bulkiness of the alkoxy tail expressed as the molar volume of substituent R, as well as with the surface tension of the compounds.
- Stopková, Lenka,Inová, Jana Gali,Uchtová, Zuzana,Márik, Jozef ?i,Andriamainty, Fils
-
-
- Arylcarbamate derivatives of 1-piperidineethanol as potent ligands for 5-HT4 receptors
-
A series of carbamate derivatives (7) of 2-(1-piperidinyl)ethyl 4- amino-5-chloro-2-methoxybenzoates, which have been described as potent agonists and antagonists of 5-HT4 receptors, were synthesized. They were evaluated using radioligand binding assays with [3H]GR 113808, a 5-HT4 receptor selective ligand, in the rat striatum and the electrically stimulated myenteric plexus longitudinal muscle of the guinea pig. In contrast to the previously described ester derivatives, a drop in the affinity for 5-HT4 receptors was observed and the compounds were inactive as agonists in the guinea pig ileum preparation. Unexpectedly, the ortho- substituted carbamates 8b,c (R' = H, RO = MeO or EtO, R'' = H) had nanomolar affinity for 5-HT4 receptors (K(i) = 8.9 ± 0.5 and 2.6 ± 0.4 nM, respectively). As reported previously, the cis- or trans-3,5-dimethyl substitution of piperidine (8n,o) was particularly favorable (K(i) = 1.1 ± 0.6 nM for both isomers). 8c is an antagonist equipotent to the 5-HT4 receptor antagonist SDZ 205-557 (1).
- Soulier, Jean-Louis,Yang, Donglai,Brémont, Béatrice,Croci, Tiziano,Guzzi, Umberto,Langlois, Michel
-
p. 1755 - 1761
(2007/10/03)
-
- 5-Hydroxytryptamine (5-HT3) Receptor Antagonists. 3. Ortho-Substituted Phenylureas
-
A novel series of potent 5-HT3 receptor antagonists, ortho-substituted phenylureas 6a-z, is described in which the 5-membered ring of the previously reported indazoles and indolines has been replaced by an intramolecular hydrogen bond.High potency was found both for carbamate 6a and urea 6b.Granatane 6c was less potent than the equivalent tropane.Phenylurea 11c lacking the ortho substituent was inactive.Whereas further substitution could not be tolerated in the aromatic ring, activity was retained with a range of O-alkyl groups, compounds 6k-t.In addition, good activity was found for ortho ester 6u and sulfonamide 6x.The ortho-substituted phenylureas can therefore be regarded as bioisosteres of the 6,5-heterocycles indole, indazole, and indoline.
- Bermudez, Jose,Dabbs, Steven,King, Frank D.
-
p. 1932 - 1935
(2007/10/02)
-
- Synthesis of isocyanates from nitroalkanes
-
A process for the preparation of aromatic isocyanates from nitroalkanes. A nitromethyl aromatic compound of the general formula: STR1 wherein R and R1 represent hydrogen, halogen, a C1 -C5 alkyl radical, a C1 -C4 alkoxy radical, nitro, isocyanato, an alkoxycarbonylamino, or nitromethyl radical, with R and R1 being the same or different, is heated in the presence of an effective amount of a Lewis acid or Bronsted acid substance to effect a dehydrogenation-isomerization reaction to yield an aromatic isocyanate of the general formula: STR2 The product of the reaction may be recovered as the aromatic isocyanate or the alcohol adduct, a carbamate.
- -
-
-