Neuroprotective poly-guanidino compounds which block presynaptic n and

Abstract

Neuroprotective drugs are disclosed with at least 3 branches extending outwardly from a center atom or group, each branch having a guanidino group at its terminus. All branches preferably should be identical, and distributed around the center atom or group in a radial manner. Three branches can be bonded to a nitrogen atom, or four branches can be coupled to a carbon atom; other center groups include stable aromatic, cycloalkyl, heterocyclic, or bicyclic structures. Starting reagents are disclosed with a center atom or group, and with reactive groups (such as primary amines or hydroxyl groups) at the ends of short 'spacer chains' bonded to the center atom or group. Reagents derived from arginine (an amino acid having a terminal guanidino group) can be bonded to these center components, using protective groups on the arginyl reagents to ensure desired final products with accessible guanidino groups at the ends of spacer chains. Alternately, guanylating agents can be used to directly convert primary amine groups at the ends of spacer chains, on starting reagents, into guanidino groups. These drugs can be injected intravenously into patients suffering from ischemic or hypoxic crises (stroke, cardiac arrest, loss of blood, suffocation, etc.), and can penetrate the blood-brain barrier and suppress the entry of calcium into CNS neurons via N-type and P/Q-type calcium channels, thereby reducing excitotoxic damage in the CNS. These drugs are also useful for suppressing other types of unwanted excessive neuronal activation, such as neuropathic pain.