ST-2560, a selective inhibitor of the Na1.7 sodium channel, affects nocifensive and cardiovascular reflexes in non-human primates.

Background And Purpose: The voltage-gated sodium channel isoform Na1.7 is a high-interest target for the development of non-opioid analgesics due to its preferential expression in pain-sensing neurons. Na1.

Discovery of Selective Inhibitors of Na1.7 Templated on Saxitoxin as Therapeutics for Pain.

The voltage-gated sodium channel isoform Na1.7 has drawn widespread interest as a target for non-opioid, investigational new drugs to treat pain. Selectivity over homologous, off-target sodium channel isoforms, which are expressed in peripheral motor neurons, the central nervous system, skeletal muscle and the heart, poses a significant challenge to the development of small molecule inhibitors of Na1.

Antinociceptive properties of an isoform-selective inhibitor of Nav1.7 derived from saxitoxin in mouse models of pain.

The voltage-gated sodium channel Nav1.7 is highly expressed in nociceptive afferents and is critically involved in pain signal transmission. Nav1.

Challenges and Opportunities for Therapeutics Targeting the Voltage-Gated Sodium Channel Isoform Na1.7.

Voltage-gated sodium ion channel subtype 1.7 (Na1.7) is a high interest target for the discovery of non-opioid analgesics.

Synthesis of the Paralytic Shellfish Poisons (+)-Gonyautoxin 2, (+)-Gonyautoxin 3, and (+)-11,11-Dihydroxysaxitoxin.

The paralytic shellfish poisons are a collection of guanidine-containing natural products that are biosynthesized by prokaryote and eukaryote marine organisms. These compounds bind and inhibit isoforms of the mammalian voltage-gated Na(+) ion channel at concentrations ranging from 10(-11) to 10(-5) M. Here, we describe the de novo synthesis of three paralytic shellfish poisons, gonyautoxin 2, gonyautoxin 3, and 11,11-dihydroxysaxitoxin.

Visualizing dermal permeation of sodium channel modulators by mass spectrometric imaging.

Determining permeability of a given compound through human skin is a principal challenge owing to the highly complex nature of dermal tissue. We describe the application of an ambient mass spectrometry imaging method for visualizing skin penetration of sodium channel modulators, including novel synthetic analogs of natural neurotoxic alkaloids, topically applied ex vivo to human skin. Our simple and label-free approach enables successful mapping of the transverse and lateral diffusion of small molecules having different physicochemical properties without the need for extensive sample preparation.

A stereoselective synthesis of (+)-gonyautoxin 3.

An asymmetric synthesis of the paralytic shellfish poison (PSP), (+)-gonyautoxin 3, is described. A unique, Rh-catalyzed amination reaction provides rapid access to the heteratom-rich, tricyclic core of the toxin, which is common to more than 30 related natural products. The completed route should facilitate the preparation of other naturally occurring PSPs and designed analogues thereof.

Expanding the substrate scope for C-H amination reactions: oxidative cyclization of urea and guanidine derivatives.

[reaction: see text] Oxidative C-H amination of N-trichloroethoxysulfonyl-protected ureas and guanidines is demonstrated to proceed in high yield for tertiary and benzylic-derived substrates. The success of these reactions is predicated on the choice of the electron-withdrawn 2,2,2-trichloroethoxysulfonyl (Tces) protecting group, the commercial catalyst Rh(2)(esp)(2) (1-2 mol %), and toluene as solvent. The frequency with which the heterocyclic imidazolidin-2-ones and 2-aminoimidazolines appear as structural elements in both natural products and therapeutically designed molecules confers these methods with a large number of potential applications.