Hydrogenation of Esters Catalyzed by Bis(<i>N</i>‑Heterocyclic Carbene) Molybdenum Complexes

A series of Mo complexes bearing inexpensive bidentate bis­(NHC) ligands have been synthesized and characterized by NMR and IR spectroscopy as well as single crystal XRD analysis. These complexes proved to be efficient for the catalytic hydrogenation of aliphatic and aromatic esters (>35 examples) operating at low catalyst loadings (0.5–2 mol %) and temperatures (80–120 °C). Various functional groups, e.g., CC double bonds, nitriles, alcohols, tertiary amines, halides, and acetals, as well as heteroaromatic substrates, lactones, and diesters, are tolerated by the optimal catalyst system. Based on NMR spectroscopic investigations, control experiments and DFT computations a non-bifunctional outer-sphere hydrogenation mechanism is proposed

Hydrogenation of Esters Catalyzed by Bis(<i>N</i>‑Heterocyclic Carbene) Molybdenum Complexes

A series of Mo complexes bearing inexpensive bidentate bis­(NHC) ligands have been synthesized and characterized by NMR and IR spectroscopy as well as single crystal XRD analysis. These complexes proved to be efficient for the catalytic hydrogenation of aliphatic and aromatic esters (>35 examples) operating at low catalyst loadings (0.5–2 mol %) and temperatures (80–120 °C). Various functional groups, e.g., CC double bonds, nitriles, alcohols, tertiary amines, halides, and acetals, as well as heteroaromatic substrates, lactones, and diesters, are tolerated by the optimal catalyst system. Based on NMR spectroscopic investigations, control experiments and DFT computations a non-bifunctional outer-sphere hydrogenation mechanism is proposed

Impact of Pharmaceutical Prophylaxis on Radiation-Induced Liver Disease Following Radioembolization

Background: Radioembolization (RE) with yttrium-90 (90Y) resin microspheres yields heterogeneous response rates in with primary or secondary liver cancer. Radiation-induced liver disease (RILD) is a potentially life-threatening complication with higher prevalence in cirrhotics or patients exposed to previous chemotherapies. Advances in RILD prevention may help increasing tolerable radiation doses to improve patient outcomes. This study aimed to evaluate the impact of post-therapeutic RILD-prophylaxis in a cohort of intensely pretreated liver metastatic breast cancer patients; Methods: Ninety-three patients with liver metastases of breast cancer received RE between 2007 and 2016. All Patients received RILD prophylaxis for 8 weeks post-RE. From January 2014, RILD prophylaxis was changed from ursodeoxycholic acid (UDCA) and prednisolone (standard prophylaxis [SP]; n = 59) to pentoxifylline (PTX), UDCA and low-dose low molecular weight heparin (LMWH) (modified prophylaxis (MP); n = 34). The primary endpoint was toxicity including symptoms of RILD; Results: Dose exposure of normal liver parenchyma was higher in the modified vs. standard prophylaxis group (47.2 Gy (17.8–86.8) vs. 40.2 Gy (12.5–83.5), p = 0.017). All grade RILD events (mild: bilirubin ≥ 21 µmol/L (but &lt;30 μmol/L); severe: (bilirubin ≥ 30 µmol/L and ascites)) were observed more frequently in the SP group than in the MP group, albeit without significance (7/59 vs. 1/34; p = 0.140). Severe RILD occurred in the SP group only (n = 2; p &gt; 0.1). ALBI grade increased in 16.7% patients in the MP and in 27.1% patients in the SP group, respectively (group difference not significant); Conclusions: At established dose levels, mild or severe RILD events proved rare in our cohort. RILD prophylaxis with PTX, UDCA and LMWH appears to have an independent positive impact on OS in patients with metastatic breast cancer and may reduce the frequency and severity of RILD. Results of this study as well as pathophysiological considerations warrant further investigations of RILD prophylaxis presumably targeting combinations of anticoagulation (MP) and antiinflammation (SP) to increase dose prescriptions in radioembolization