Photoremovable Protecting Groups

Photoremovable protecting groups (PPGs) (also often called photocages in the literature) are used for temporary inactivation of biologically active substrates. By photoirradiation the PPG could be cleaved off and the biological activity could be restored on-demand, with a high spatiotempo- ral precision. The on-site liberation of the biologically active substrate could be exploited for studying dynamic biological processes or for designing targeted pharmacological interventions in vitro or in vivo. Several chemical scaffolds have been described and tested as PPGs, operating at different wavelengths. The scope of potential substrates is very broad, spanning from small molecules to proteins. In a wider context, PPGs could be used for the design of various light-responsive materials as well, for diverse applications

Targeted Cancer Therapy Using Compounds Activated by Light

Cancer chemotherapy is affected by a modest selectivity and toxic side effects of pharmacological interventions. Among novel approaches to overcome this limitation and to bring to therapy more potent and selective agents is the use of light for selective activation of anticancer compounds. In this review, we focus on the anticancer applications of two light-activated approaches still in the experimental phase: photoremovable protecting groups (“photocages”) and photoswitches. We describe the structural considerations behind the development of novel compounds and the plethora of assays used to confirm whether the photochemical and pharmacological properties are meeting the stringent criteria for an efficient in vivo light-dependent activation. Despite its immense potential, light activation brings many challenges, and the complexity of the task is very demanding. Currently, we are still deeply in the phase of pharmacological tools, but the vivid research and rapid development bring the light of hope for potential clinical use

A terc-amino effektus vizsgálata és kiterjesztése: új típusú, biológiailag aktív policiklusos vegyületek előállítása = The study and the extension of the tert-amino effect: Synthesis of new types of polycyclic compounds with biological activities

1. Vizsgáltuk a terc-amino effektus 2. típusának kiterjesztését a reakcióban résztvevő vinil és terc-amino csoportot két külön gyűrűn tartalmazó (kondenzált) bi- és triaril - bifenil/fenilpiridazin, trifenil/difenilpiridazin, naftalin illetve fenilnaftalin - modellvegyületekre; a gyűrűzárási reakciók révén új azepin-, azocin-, azonin- és azecin-anellált gyűrűrendszereket állítottunk elő. E munkánk révén a terc-amino effektus az eddigi ismeretek szerinti alkalmazását lényegesen bővítettük. 2. Antimaláriás hatásirányban nemzetközi együttműködésben vizsgáltuk azocinszármazékok, illetve indolokinolin alkaloidok bi- és triciklusos analógjainak aktivitását. Ez utóbbiak közül két származék is jelentős in vitro aktivitást mutatott. 3. SSAO hatásirányban vizsgáltuk a terc-amino effektussal nyert diciano-szubsztituált azaheterociklusokból előállított aminometil származékok, illetve további vegyületcsaládok (oxim típusú vegyületek, aminometil-piridazinok) aktivitását; együttműködésben kiválasztott SSAO-gátlók további in vivo vizsgálatára került sor gyulladásos modelleken. E vegyületek egyike (SZV-1287) mind in vitro, mind in vivo jelentős SSAO-gátló és gyulladáscsökkentő hatást fejt ki; fejlesztéséről a közeljövőben döntünk. | 1. Novel extensions of the type 2 tert-amino effect have been studied to compounds having the interacting vinyl and tert-amino moieties on two different rings. Namely, cyclizations of bi- and triaryl - biphenyl/phenylpyridazine, triphenyl/diphenylpyridazine, napthalene and phenylnapthalene - model systems were studied, affording novel azepine-, azocine-, azonine- and azecine-fused ring systems. Our studies facilitate novel applications of the tert-amino effect as compared to cyclizations described thus far. 2. In the frame of an international collaboration, the antimalarial activity of azocine derivatives, and bi- and tricyclic analogues of indoloquinoline alkaloids were studied. Two representatives of the latter group exhibited substantial in vitro activity. 3. SSAO activity of aminomethyl derivatives obtained from dicyano-substituted azaheterocycles synthesized via tert-amino effect cyclization and further classes of compounds (oxime derivatives, aminomethyl-pyridazines) were studied; in collaboration in vivo activity of selected SSAO inhibitors were studied in inflammatory models. On selected derivative (SZV-1287) exhibited substantial in vitro and in vivo SSAO inhibitor and anti-inflammatory activity; we are to decide on its further development

Effects of Chemical Structures Interacting with Amine Oxidases on Glucose, Lipid and Hydrogen Peroxide Handling by Human Adipocytes

Benzylamine is a natural molecule present in food and edible plants, capable of activating hexose uptake and inhibiting lipolysis in human fat cells. These effects are dependent on its oxidation by amine oxidases present in adipocytes, and on the subsequent hydrogen peroxide production, known to exhibit insulin-like actions. Virtually, other substrates interacting with such hydrogen peroxide-releasing enzymes potentially can modulate lipid accumulation in adipose tissue. Inhibition of such enzymes has also been reported to influence lipid deposition. We have therefore studied in human adipocytes the lipolytic and lipogenic activities of pharmacological entities designed to interact with amine oxidases highly expressed in this cell type: the semicarbazide-sensitive amine oxidase (SSAO also known as PrAO or VAP-1) and the monoamine oxidases (MAO). The results showed that SZV-2016 and SZV-2017 behaved as better substrates than benzylamine, releasing hydrogen peroxide once oxidized, and reproduced or even exceeded its insulin-like metabolic effects in fat cells. Additionally, several novel SSAO inhibitors, such as SZV-2007 and SZV-1398, have been evidenced and shown to inhibit benzylamine metabolic actions. Taken as a whole, our findings reinforce the list of molecules that influence the regulation of triacylglycerol assembly/breakdown, at least in vitro in human adipocytes. The novel compounds deserve deeper investigation of their mechanisms of interaction with SSAO or MAO, and constitute potential candidates for therapeutic use in obesity and diabetes

Synthesis of 8-aminoquinoline chelating moieties for chemosensor molecules

8-Aminoquinolines are useful molecular motifs for ion sensors. To encourage chemosensor development, new building blocks containing these motifs are essential. 8-Aminoquinoline-2-carbaldehydes are proposed as useful building blocks since their aldehyde group offers the possibility for further transformations. We present a general method for the preparation of these compounds starting from commercially available 8-bromo-2- methylquinoline. Different sidechains for fine-tuning their affinity and selectivity were introduced by a microwave-aided N-arylation using Pd(0) and P-ligands; the desired products were achieved by oxidation. An alternative method is also presented when the product shows high affinity towards the catalyst limiting the effectiveness of the Pd-catalysed the N-arylation

Novel 1,4-benzoxazine and 1,4-benzodioxine inhibitors of angiogenesis.

Esters of 1,4-benzoxazine and 1,4-benzodioxine compounds 1 and 10, which combine thrombin inhibitory and GPIIb/IIIa antagonistic activity in one molecule are shown to inhibit endothelial cell migration and tube formation in vitro and angiogenesis in the chicken chorioallantoic membrane (CAM) assay. The corresponding carboxylic acids 1 (R2 = H) and 11 were devoid of antiangiogenic activity, most probably due to their insufficient entry into the cell. Although thrombin inhibition remains the most probable explanation for their inhibition of angiogenesis, VEGFR2 kinase assay suggest that other targets such as VEGFR2 might be involved

Evolution of model proteins on a foldability landscape

We model the evolution of simple lattice proteins as a random walk in a fitness landscape, where the fitness represents the ability of the protein to fold. At higher selective pressure, the evolutionary trajectories are confined to neutral networks where the native structure is conserved and the dynamics are non self-averaging and nonexponential. The optimizability of the corresponding native structure has a strong effect on the size of these neutral networks and thus on the nature of the evolutionary process. Proteins 29:461–466, 1997. © 1997 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38527/1/6_ftp.pd

Die "Innige Seele" in einer Mainzer Handschrift

Übersehen wurde bislang, dass die "Innige Seele" aus der Gruppe der Dialoggedichte "Kreuztragende Minne" in der Handschrift der Stadtbibliothek Mainz Hs I 327 überliefert ist und von FWE Roth abgedruckt wurde. Das lange vermisste Tafelgemälde aus der Klause Kamp gegenüber von Boppard befindet sich heute in der Sammlung Thyssen-Bornemisza in Madrid. Ferdinand Wilhelm Emil Roth, Mittheilungen aus Handschriften und älteren Druckwerken. In: Zeitschrift für deutsche Philologie 26 (1894), S. 58-70,..