Targeting calcium signaling in cancer therapy.

Gold complexes containing organoselenium and organotellurium ligands

The challenge of prebiotic chemistry is to trace the syntheses of life's key building blocks from a handful of primordial substrates. Here we report a forward-synthesis algorithm that generates a full network of prebiotic chemical reactions accessible from these substrates under generally accepted conditions. This network contains both reported and previously unidentified routes to biotic targets, as well as plausible syntheses of abiotic molecules. It also exhibits three forms of nontrivial chemical emergence, as the molecules within the network can act as catalysts of downstream reaction types; form functional chemical systems, including self-regenerating cycles; and produce surfactants relevant to primitive forms of biological compartmentalization. To support these claims, computer-predicted, prebiotic syntheses of several biotic molecules as well as a multistep, self-regenerative cycle of iminodiacetic acid were validated by experiment.

https://science.sciencemag.org/content/sci/369/6511/eaaw1955.full.pdf

Synthetic connectivity, emergence, and self-regeneration in the network of prebiotic chemistry

A series of both mono- and dinuclear gold(I) phosphine complexes containing monoanionic seleno- and thiosemicarbazones as ligands were prepared and fully characterized by spectroscopic methods and, in some cases, by single crystal X-ray diffraction. The in vitro anti-malaria activity of some of these compounds was investigated in chloroquine sensitive strains of Plasmodium falciparum. The IC50 results show that the sulfur containing compounds exhibit activity similar to that of chloroquine, whilst the selenium derivatives display only moderate anti-malaria activity.

Synthesis, structures and anti-malaria activity of some gold(I) phosphine complexes containing seleno- and thiosemicarbazonato ligands

The first organocatalytic asymmetric inverse-electron-demand 1,3-dipolar cycloaddition (IED 1,3-DC) of N,N′-cyclic azomethine imines has been established in the presence of chiral phosphoric acid. This approach assembles N,N′-cyclic azomethine imines and o-hydroxystyrenes into chiral N,N-bicyclic pyrazolidin-3-one derivatives with the creation of two stereogenic centers, one of which is quaternary, in excellent diastereoselectivities and good enantioselectivities (up to >95:5 dr, 88:12 er). The investigation of the activation mode of the reaction revealed that the dual hydrogen-bonding interaction between the two substrates and the catalyst together with the conjugative effect initiated by the o-hydroxyl group played a crucial role in the designed IED 1,3-DC. This study will not only greatly enrich the underdeveloped research potential of catalytic asymmetric IED 1,3-DCs but will also facilitate the design of other enantioselective IED 1,3-DCs based on different activation modes.

Organocatalytic Asymmetric Inverse-Electron-Demand 1,3-Dipolar Cycloaddition of N,N′-Cyclic Azomethine Imines

Synthesis and SERCA activities of structurally simplified cyclopiazonic acid analogues.

Synthesis and structures of gold(I) phosphine complexes containing monoanionic selenocarbamate ester ligands

A series of both mono- and dinuclear gold(I) phosphine complexes containing deprotonated N-phenyl-O-methylselenocarbamate of the type [AuSeC(OMe) = NPh(P)] and [Au 2 SeC(OMe) = NPh 2 (PP)] (P = PPh 3 , P(o-tolyl) 3 , PTA; PP = dppm, dppe, dppp, dppf) were prepared and characterized by spectroscopic techniques. The X-ray crystal structure of SeC(OMe)═N(H)Ph is also reported and shows the molecule to exist in the E-conformation. Centrosymmetrically related dimers associate in the crystal structure by N─H…Se interactions.

Daniel Gallenkamp

Papers

Synthesis and SERCA activities of structurally simplified cyclopiazonic acid analogues.

Synthesis and structures of gold(I) phosphine complexes containing monoanionic selenocarbamate ester ligands

Gold(I) Phosphine Complexes Containing Selenocarbamate Esters: Crystal and Molecular Structure of N-phenyl-O-methylselenocarbamate