Chiral, triformylphenol-derived salen-type [4 + 6] organic cages.

A one-pot synthesis of chiral [4 + 6] tetrahedral cage compounds containing a salen fragment on each face is presented. The formation of the [4 + 6] products remains in contrast to the reaction of 1,3,5-triformylphloroglucinol with chiral diamines where [2 + 3] keto-enamine pseudocyclophanes are formed exclusively. The presence of OH groups determines the structural and spectroscopic properties of these cage compounds while a change in the reaction conditions facilitates the isolation of the microcrystalline products of the specific surface area varying from 5 to 578 m(2) g(-1).

Surprising pharmacological activity of analogues designed by substitution of position 3 in arginine vasopressin (AVP) and 8-D-arginine vasopressin with L-2-napthylalanine.

In an attempt to develop more active and selective analogues of arginine vasopressin (AVP), two peptides have been designed, synthesized and tested for vasopressor (V1-receptors) and antidiuretic (V2-receptors) activities. We also estimated the uterotonic and anti-uterotonic activities of these compounds in-vitro. The first peptide, [(L-2-Nal)3] AVP is a highly active V2-agonist. The second analogue, [(L-2-Nal)3, (D-Arg)R]VP is among the most potent antagonists of the vasopressor response to AVP. Moreover, it is the first V1-antagonist devoid of anti-uterotonic activity. High antipressor potency of the second peptide was achieved without modification of position 1.

[Aztreonam--new antibiotic for treating infections caused by gram-negative aerobic bacteria]. / Aztreonam--nowy antybiotyk w leczeniu zakazen wywolywanych przez gram-ujemne bakterie tlenowe.

Aztreonam is the first synthetic monobactam used in practical medicine. It is effective in Gram-negative aerobe infections. It inhibits the growth of most Enterobacteriaceae in concentrations below 2 mg/ml, and of Pseudomonas aeruginosa below 16 mg/ml. It shows a widespread, distribution achieving effective therapeutic concentration there, where infections are seen most frequently. The half-life is from 1.6 to 2.0 hours. It can be administered to patients every 8 and 12 hours in single parenteral doses of 0.5, 1.0, and 2.0 g. Aztreonam is a non-toxic antibiotic, a weak hapten with slight allergenicity. It has found therapeutic use together with the antibiotics directed against aerobic and anaerobic bacterial Gram-positive flora, and it is used in the therapy directed against infections with Gram-negative aerobes. It is an effective antibiotic in nosocomial infections, in oncological patients with neutropenia, and in elderly patients.