ABSTRACT
Phenotypic screening of an annotated small molecule library and initial SAR studies identified compound 2 as a robust enhancer of progranulin secretion. Detailed SAR development on conformationally restricted carbamate isosteres led to the identification of compound 60 with a 3-fold improvement in BV-2 potency and a 9-fold decrease in hERG inhibition over compound 2, substantially improving this important margin of safety relative to compound 2.
Subject(s)
Frontotemporal Dementia , Intercellular Signaling Peptides and Proteins , Humans , ProgranulinsABSTRACT
Two valuable forensic tools based on enzyme-linked immunoassays (ELISAs) for the analysis of 17α-methylated steroids were developed using haptens of stanazolol and its conjugates with biotin. Haptens containing terminal carboxylic group were conjugated to bovine serum albumin (BSA), rabbit serum albumin (RSA) or ovalbumin (OVA). Eight batches of antisera (RAbs) obtained by immunization of rabbits were tested in an indirect competitive ELISA system using immobilization of RSA conjugate (RSA/hapten) and competitor immobilization of the biotinylated conjugate (AB-ELISA) to avidin (avidin/hapten). The best results were achieved with the RAb 212 antibodies in RSA/ST-3 and avidin/ST-10 assembled variants. For the RSA/ST-3 system, an IC50 of 0.3 ng/mL and a detection limit of 0.02 ng/mL were measured. In case of avidin/ST-10 variant, IC50 was of 3.9 ng/mL and a detection limit of 0.57 ng/mL were obtained. The effect of solvent was tested as well as the stability of coated microtiter plates over four-month period. The cross-reactivity of the developed assays with other anabolic steroids was tested and high sensitivity towards 17α-methylated steroids was observed. RSA/ST-3 assay showed significant cross-reactivity with 17α-methyltestosterone (81.2%), oxymetholone (30.4%), methandienone (10.0%) and methyl dihydrotestosterone (7.7%). Similarly, in the avidin/ST-10 assay, 17α-methyltestosterone (34.5%), mestanolone (32.1%), oxymetholone (22.7%), methandienone (14.2%), 9-dehydromethyltestosterone (12.5%) and oxandrolone (1.2%) exhibited high cross-reactivity. The functionality of the developed systems was verified by the successful identification of a series of 17α-methylated anabolic steroids in a set of real samples including pharmaceutical preparations seized by the Police of the Czech Republic on the black market.
Subject(s)
Enzyme-Linked Immunosorbent Assay , Forensic Medicine , Stanozolol/chemistry , Testosterone Congeners/analysis , Animals , Calibration , Cattle , Immune Sera , Methylation , Molecular Conformation , Rabbits , Serum Albumin/chemistry , StereoisomerismABSTRACT
Syntheses of novel semi-orthogonally protected CycloTriVeratrilene (CTV) analogues with enhanced water solubility, that is 3 and 4, derived from the previously described CTV scaffold derivative 2 are described here. These scaffolds 2-4 enabled a sequential introduction of three different complementarity determining region (CDR) mimics via Cu(i)-catalysed azide-alkyne cycloaddition towards medium-sized protein mimics denoted as "synthetic antibodies". The highly optimised sequential introduction enabled selective attachment of three different CDR mimics in a one-pot fashion. This approach of obtaining synthetic antibodies, demonstrated by the synthesis of paratope mimics of monoclonal antibody infliximab (Remicade®), provided a facile access to a range of (highly) pre-organised molecules bearing three different (cyclic) peptide segments and may find a wide range of applications in the field of protein-protein interaction disruptors as well as in the development of synthetic vaccines or lectin mimics. The prepared synthetic antibodies were tested for their affinity towards tumour necrosis factor alpha using surface plasmon resonance and synthetic antibodies with micromolar affinities were uncovered.
ABSTRACT
The synthesis of a semi-orthogonally protected CycloTriVeratrilene (CTV) scaffold derivative as well as the sequential introduction of three different peptide loops onto this molecular scaffold via Cu(I)-catalyzed azide alkyne cycloaddition towards a medium-sized protein mimic is described. This approach for the construction of medium-sized protein mimics is illustrated by the synthesis of a paratope mimic of the monoclonal antibody Infliximab (Remicade®) and provides access to a range of highly pre-organized molecular constructs bearing three different peptide segments. This approach may find wide applications for development of protein-protein interaction disruptors as well as synthetic vaccines.
Subject(s)
Peptides, Cyclic/chemical synthesis , Polycyclic Compounds/chemistry , Alkynes/chemistry , Azides/chemistry , Catalysis , Copper/chemistry , Cycloaddition Reaction , Infliximab/chemistry , Infliximab/metabolism , Peptides, Cyclic/chemistryABSTRACT
17ß-O-Hemisuccinates of typical representatives of Anabolic-Androgenic Steroids, 17ß-hydroxy-17-methylandrostan-4-en-3-one, 17ß-hydroxy-17-methyl-2-oxa-5α-androstan-3-one, 17ß-hydroxy-17-methyl-5α-androstano-[3,2-c]pyrazole, were prepared. Several methods for the hemisuccinate preparation were tested. The indirect method using 1-ethyl-3-(dimethylaminopropyl)carbodiimide coupling reagent to form an ester bond of steroid with 2-(trimethylsilyl)ethyl hydrogen butanedioate was finally applied. Using the selectively removable protecting group, the desired hemisuccinates of steroids bearing tertiary alcohol group were obtained.
