The success of gene therapy depends on safe and effective gene carriers. Despite being widely used, synthetic vectors based on poly(ethylenimine) (PEI), poly(l-lysine) (PLL), or poly(l-arginine) (poly-Arg) are not yet fully satisfactory. Thus, both improvement of established carriers and creation of new synthetic vectors are necessary. A series of biodegradable arginine-based ether-ester polycations was developed, which consists of three main classes: amides, urethanes, and ureas. Compared to that of PEI, PLL, and poly-Arg, much lower cytotoxicity was achieved for the new cationic arginine-based ether-ester polymers. Even at polycation concentrations up to 2 mg/mL, no significant negative effect on cell viability was observed upon exposure of several cell lines (murine mammary carcinoma, human cervical adenocarcinoma, murine melanoma, and mouse fibroblast) to the new polymers. Interaction with plasmid DNA yielded compact and stable complexes. The results demonstrate the potential of arginine-based ether-ester polycations as nonviral carriers for gene therapy applications.

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Das 3‐Octin‐diol (I) wird durch Triäthylsilan (II) infolge einer zuerst stattfindenden Meyer‐Schuster‐Umlagerung in die Carbonylverbindung (III) übergeführt, während das 3‐Hexindiol (IV) mit (II) sowohl zu einer Carbonylverbindung (V) wie auch, infolge normaler Addition an die Dreifachbindung, zu (VI) reagiert.

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Little has been published about carbohydrates containing heterocyclic compounds. However, such compounds are definitely of practical interest for synthesizing new types of 1,2-trans-glucosides [1][2][3].We propose a convenient method for synthesizing new types of heterocyclic derivatives of 1,2-trans-glucosides. Condensation of 1-chloro-2,3,4,6-tetra-O-acetyl-α-D-glucopyranose (1) with 4,4,8,8-tetramethyl-2,3,6,7-dibenzo-9-oxabicyclo-(3,3,1)-nonan-1-N-amino-5-ol (2); 4,4,8,8-tetramethyl-2,3,6,7-dibenzo-9-oxabicyclo-(3,3,1)-nonan-1-Nmethylamino-5-ol (3); 4,4,8,8-tetramethyl-2,3,6,7-dibenzo-9-oxabicyclo-(3,3,1)-nonan-1-N-ethylamino-5-ol (4); and 4,4,8,8-tetramethyl-2,3,6,7-dibenzo-9-oxabicyclo-(3,3,1)-nonan-1-N-tryptamin-5-ol (5) at room temperature in the presence of freshly prepared Ag 2 CO 3 catalyst in ether solution produced 6-9, respectively, according to Scheme 1.The course of reactions was monitored by TLC. The reactions took 14-16 h to produce mainly 1,2-trans-glycosides 6-9 although small quantities of the 1,2-cis-isomers were also observed. The products were yellow crystalline compounds that were soluble in CHCl 3 and alcohol (MeOH, EtOH). The yields of 2-5 decreased as the radical bonded to the heterocycle increased. This was probably due to steric factors.These are nucleophilic substitution reactions that occur through an S N 2 mechanismm. The direction of the reaction depends on the relative configuration of C 1 and C 2 in the starting acylated chloroglucose and on the acceptor of the released HCl. Condensation of 1,2-cis-acylglycosylhalides with alcohols in the presence of Ag 2 CO 3 occurred mainly with C 1 configuration inversion, resulting in formation of 1,2-trans-glycosides [4].We performed quantum-chemical calculations using CS Mopac2000 Version 1.11 in order to justify theoretically the direction of the condensation of 1-chloro-2,3,4,6-tetra-O-acetyl-α-D-glucopyranose with the dibenzooxabicycloamine derivatives. Compounds were optimized before each AM1 (Austin Model 1) calculation by minimizing the energy using molecular mechanics (MM) and quantum-chemical methods [5]. 1 2 -5 6 -9 R = -NH 2 (2, 6); -NHCH 3 (3, 7); -NHC 2 H 5 (4, 8); N H −NH−CH 2 −CH 2 (5, 9)