Abstract: The present invention is directed to the use of conantokin peptides, conantokin peptide derivatives and conantokin peptide chimeras, referred to collectively as conantokins, having 10-30 amino acids, including preferably two or more &ggr;-carboxyglutamic acid residues, for the treatment of neurologic and psychiatric disorders, such as pain, e.g., as an analgesic agent.

Abstract: The present invention is directed to the use of conantokin peptides, conantokin peptide derivatives and conantokin peptide chimeras, referred to collectively as conantokins, having 10-30 amino acids, including preferably two or more &ggr;-carboxyglutamic acid residues, for the treatment of neurologic and psychiatric disorders, such as anticonvulsant agents, neuroprotective agents or analgesic agents.

Abstract: Muscarinic M.sub.2 receptor ligands are described which are suitable for the treatment of neurological disorders, and which may be administered with minimal side-effects. A method of synthesis of these compounds is also described.

Abstract: Conjugates of fluorescent labels with specific, selective, and high affinity ligands for receptors have been synthesized and used to directly measure binding to receptors.

Abstract: Drug delivery systems have been developed based on the formation of diketopiperazine (or analogs) microparticles. In the preferred embodiment the microparticle is stable at low pH and disintegrates at physiological pH, and is particularly useful for oral drug delivery. In other embodiments, the microparticles are stable at high pH and disintegrate at neutral or basic pH, or are stable at neutral pH and disintegrate at high or low pH. In the most preferred embodiment the microparticles are formed in the presence of the drug to be delivered, for example, insulin, felbamate, calcitonin or heparin. The diketopiperazine synthetic intermediates are preferably formed by cyclodimerization to form diketopiperazine derivatives at elevated temperatures under dehydrating conditions, functionalized on the side chains, and then precipitated with drug to be incorporated into microparticles.

Abstract: Conjugates of fluorescent labels with specific, selective, and high affinity ligands for receptors have been synthesized and used to directly measure binding to receptors. In the examples, fluorescein conjugates of the high-affinity benzodiazepine receptor ligands Ro 15-1788 and Ro 7-1986 were synthesized. The binding of these fluorescent ligands (BD 621, BD 623 and BD 607) to benzodiazepine receptors was characterized by direct fluorescence measurement. Both the equilibrium dissociation constants (K.sub.D) of BD 621 and BD 607 and the maximum number of binding sites (B.sub.max) estimated by fluorescence monitoring were consistent with values obtained by using radioligand binding techniques. The binding of BD 621 and BD 607 assessed by fluorescence measurement was reversible, abolished by photoaffinity labeling with Ro 15-4513, and unaffected by a variety of substances that do not bind to benzodiazepine receptors.

Abstract: The present invention is directed to compounds useful as probes for characterizing and studying the adenosine A.sub.2 receptor. The present invention is also directed to methods of treating central nervous system disorders and cardiovascular disorders which include treating hypertension and thrombosis by administering said compounds.