- Regioselective covalent modification of hemoglobin in search of antisickling agents
-
Although the molecular defect in sickle hemoglobin that produces sickle cell disease has been known for decades, there is still no effective drug treatment that acts on hemoglobin itself. In this work, a series of diversely substituted isothiocyanates (R-NCS) were examined for their regioselective reaction with hemoglobin in an attempt to alter the solubility properties of sickle hemoglobin. Electrospray mass spectrometry, molecular modeling, X-ray crystallography, and conventional protein chemistry were used to study this regioselectivity and the resulting increase in solubility of the modified hemoglobin. Depending on the attached R-group, the isothiocyanates were found to react either with the Cysβ93 or the N-terminal amine of the α-chain. One of the most effective compounds in the series, 2-(N,N-dimethylamino)ethyl isothiocyanate, selectively reacts with the thiol of Cysβ93 which, in conjunction with the cationic group, was seen to perturb the local hemoglobin structure. This modified HbS shows an approximately 30% increase in solubility for the fully deoxygenated state, along with a significant increase in oxygen affinity. This compound and a related analogue appear to readily traverse the erythrocyte membrane. A discussion of the relation of these structural changes to inhibition of gelation is presented. The dual activities of increasing HbS oxygen affinity and directly inhibiting deoxy HbS polymerization, in conjunction with facile membrane traversal, suggest that these cationic isothiocyanates show substantial promise as lead compounds for development of therapeutic agents for sickle cell disease.
- Park, Soobong,Hayes, Brittany L.,Marankan, Fatima,Mulhearn, Debbie C.,Wanna, Linda,Mesecar, Andrew D.,Santarsiero, Bernard D.,Johnson, Michael E.,Venton, Duane L.
-
p. 936 - 953
(2007/10/03)
-
- SUBSTITUTED (AMINOIMINOMETHYL OR AMINOMETHYL) BENZOHETEROARYL COMPOUNDS
-
This invention is directed to an (aminoiminomethyl or aminomethyl) benzoheteroaryl compound of formula I which is useful for inhibiting the activity of Factor Xa by combining said compound with a composition containing Factor Xa. The present invention is also directed to compositions containing compounds of the formula I, methods for their preparation, their use, such as in inhibiting the formation of thrombin or for treating a patient suffering from, or subject to, a disease state associated with a physiologically detrimental excess amount of thrombin.
- -
-
-
- Anthelmintic 1-(substituted phenyl)-3-alkanimidoyl ureas
-
The compounds of this invention are novel imidoylureas having anthelmintic activity and imidoylthioureas having antifertility activity. They are prepared by the reaction of appropriate amidines with appropriate isocyanates or isothiocyanates.
- -
-
-