Negishi Cross-Coupling in the Preparation of Benzyl Substituted Pyrrolo[2,3-d]pyrimidine Based CSF1R Inhibitors

The colony-stimulating factor 1 receptor (CSF1R) is a protein kinase emerging as an attractive target with clinical relevance in cancer, CNS and inflammatory diseases. Molecular docking experiments followed by synthesis and structure–activity relationship have been used to identify low molecular weight structures as promising hits for lead optimization. These molecules are synthesized from a 4-chloro-6-iodo-pyrrolo[2,3-d]pyrimidine building block using Negishi and Suzuki–Miyaura cross-coupling reactions in high yields. Several inhibitors possessed excellent enzymatic potency, and the parent compound preferably binds to the autoinhibited form of CSF1R. Cellular and in vivo profiling indicate that further tuning of drug structure is needed prior to efficacy studies.     

Linear-temperature programmed pyrolysis of thermoresistant polymers - mass and FTIR spectrometries I. Experimental; aromatic polyethers and polyetherketones

During thermal decomposition, most of the thermo-resistant polymers leave a considerable fraction of the original mass behind, consisting mainly of a carbonaceous material. The gases evolved are, to the largest part, low-molecular (H₂O, CO₂, CO, NH₃, HCN, hydrocarbons); they are formed during polycondensation processes. The rate of heating strongly influences the degradation mechanism and thus the composition of the gaseous pyrolyzate. Rapid heating i.v. to the maximum temperature chosen frequently favors the formation of heavy fragments. These can be identified by field-ionization or low-voltage mass spectrometry; they usually allow conclusions on the composition of the original polymer. Slow, temperature-controlled heating allows rearrangement and polycondensation reactions in the polymer. A study of the processes going on in the residue during temperature-controlled heating is important with regard to the behavior of thermoresistant polymers under real conditions. An elegant method of continuous residue analysis is FTIR spectrometry. A heatable IR cell designed in our institute allows the study of both gaseous pyrolyzate and solid residue in separate experiments. The time needed for the measurement of one spectrum (from 20 scans) was 36 s. This, with a heating rate of 5 K/min, corresponds to a temperature resolution of 3 K/spectrum. Results are given for aromatic polyethers and polyetherketones.     

A Complete Triad of Zero-Valent 17-Electron Monoradicals of Group 7 Elements Stabilized by m-Terphenyl Isocyanides

The first consistent series of mononuclear 17-electron complexes of three Group 7 elements has been isolated in crystalline form and studied by X-ray diffraction and spectroscopic methods. The paramagnetic compounds have a composition of [M⁰(CO)(CNp-F-Ar^DArF2)₄] (M=Mn, Tc, Re; Ar^DArF2=2,6-(3,5-(CF₃)₂C₆H₃)₂C₆H₂F) and are stabilized by four sterically encumbering isocyanides, which prevent the metalloradicals from dimerization. They have a square pyramidal structure with the carbonyl ligands as apexes. The frozen-solution EPR spectra of the rhenium and technetium compounds are clearly anisotropic with large ⁹⁹Tc and ^185,187Re hyperfine interactions for one component. High-field EPR (Q band and W band) has been applied for the elucidation of the EPR parameters of the manganese(0) complex.