Exchange assay), non-teratogenic, and devoid of reproductive toxicity in mice [42]. After oral application in rats, the half-lethal dose (LD50 ) was greater than 5000 mg/kg ( 25 mmol/kg), apparently the highest dose tested. For comparison, 5-fluorouracil was optimistic in all genotoxicity assays and half-lethal in rats at 230 mg/kg ( 1.eight mmol/kg) [43]. Actinomycin D, in turn, has been reported to be half-lethal in rats currently at 7.2 mg/kg ( 0.0057 mmol/kg) following oral administration [44]. The present study has two significant limitations. Very first, in vivo information from an accepted animal model are usually not readily available however. Such data would be important for the assessment from the selectivity of the presented chain-transfer agents for tumor cells vs. standard cells in a wholebody context. Second, the chemical mechanism of chain-transfer catalysis elaborated just before in fibroblasts [17] was not rechecked in the presently investigated tumor cells. Nevertheless, since the original report [17] has shown coherent effects in two rather various experimental systems (diploid human lung fibroblasts and C. elegans nematodes), it appears plausible that a related mechanism also accounts for the right here described cytotoxicity in tumor cells.Molecules 2021, 26,9 of4. Materials and Procedures 4.1. Chemical substances and Reagents The investigational thiols and thioethers were obtained in the following sources: octane-1-thiol (8SH; CAS 111-88-6) was from Sigma-Aldrich, St. Louis, MO, USA (#471836, purity 98.5 ); decane-1-thiol (10SH; CAS 143-10-2) was from Cyclopenin Epigenetic Reader Domain Sigma-Aldrich (#705233, purity 99 ); dodecane-1-thiol (12SH; CAS 112-55-0) was from Sigma-Aldrich (#471364, purity 98 ); tetradecane-1-thiol (14SH; CAS 2079-95-0) was from Sigma-Aldrich (#87193, purity 98 ); hexadecane-1-thiol (16SH; CAS 2917-26-2) was from Alfa Aesar, Ward Hill, MA, USA (#L15099, purity 97 ); octadecane-1-thiol (18SH; CAS 2885-00-9) was from Sigma-Aldrich (#O1858, purity 98 ); 1-methylsulfanyldodecane (12SMe; CAS 3698-89-3) was from Sigma-Aldrich (#641480, purity 97 ). The lipophilicities of these compounds had been calculated as Aranorosin medchemexpress octanol-water partition coefficients (logP) with all the ChemPropPro tool that’s part of the ChemBio3D 13.0 software package (PerkinElmer, Waltham, MA, USA). Reference cytostatic drugs have been purchased in the following suppliers: doxorubicin hydrochloride (Dox; CAS 25316-40-9) was from Cayman Chemical compounds, Ann Arbor, MI, USA (#15007; purity 98 ); actinomycin D (Act; CAS 50-76-0) was from Cayman Chemicals (#11421; purity 95 ); 5-fluorouracil (FU; CAS 51-21-8) was from Sigma-Aldrich (#F6627; purity 99 ); hydroxyurea (HU; CAS 127-07-1) was from Sigma-Aldrich (#H8627; purity 98 ). All typical laboratory chemicals and solvents have been from Sigma-Aldrich. Cell culture reagents including DMEM (#41965-039), sodium pyruvate (#11360-039), penicillin/streptomycin (#15240-062), and trypsin/EDTA (#15400-054) had been from Gibco, Carlsbad, CA, USA, except for FCS (#S181BH from Biowest, Nuaill France), PBS (#D8537 from Sigma-Aldrich), and antibiotic-antimycotic answer (#A5955 from Sigma-Aldrich). Cell culture dished and flasks were from TPP, Trasadingen, Switzerland, and used with no further surface remedy. 4.two. Cell Lines and Their Cultivation SY5Y human neuroblastoma cells have been from LGC Requirements, Teddington, UK. Hela human cervical carcinoma cells were from the stocks in the Institute for Pathobiochemistry with the University of Mainz and have been authenticated by short tandem repeat (STR) analysis as described [45]. HEK293 immo.