Nasal administration of carbamazepine using chitosan microspheres: in vitro/in vivo studies.

The nasal route is used both for local therapies and, more recently, for the systemic administration of drugs, as well as for the delivery of peptides and vaccines. In this study the nasal administration of Carbamazepine (CBZ) has been studied using microspheres constituted by chitosan hydrochloride (CH) or chitosan glutamate (CG). Blank microspheres were also prepared as a comparison. The microspheres were produced using a spray-drying technique and characterized in terms of morphology (scanning electron microscopy, SEM), drug content, particle size (laser diffraction method) and thermal behaviour (differential scanning calorimetry, DSC). In vitro drug release studies were performed in phosphate buffer (pH 7.0). In vivo tests were carried out in sheep using the microparticles containing chitosan glutamate, chosen on the basis of the results of in vitro studies. The results were compared to those obtained after the nasal administration of CBZ (raw material) alone. For the evaluation of in vivo data statistical analysis was carried out using the unpaired t-test. Spray-drying was a good technique of preparation of CBZ-loaded microspheres. The loading of the drug into the polymeric network always led to an increase in the dissolution rate compared to CBZ raw material. The microspheres obtained using chitosan glutamate had the best behaviour both in vitro and in vivo. They increased the drug concentration in the serum when compared to the nasal administration of the pure drug (Cmax 800 and 25 ng/ml for microspheres and pure drug, respectively). The results obtained indicate that the loading of CBZ in chitosan glutamate microspheres increases the amount of the drug absorbed through the nose.

Antispasmodic activity of tert-aminoalkylderivatives of 3-benzyl-, 3-benzylaza- and 3-benzyldiazaquinoxalinones.

Tert-aminoalkylderivatives of quinoxalin-2-ones, aza- and diazaquinoxalin-2-ones bearing in position 3 a benzyl group were assayed to evaluate the antispasmodic activity. The tested compounds exhibited moderate aspecific antispastic properties that do not warrant further investigation.

Pyridazine N-oxides. II. Synthesis and in vitro antimicrobial evaluation of 3-chloro-4-carbamoyl-5-aryl-6-methyl-pyridazine N-oxides.

As a part of a research project on antimicrobial agents, various novel carbamoyl derivatives of pyridazine-N-oxides 7a-j were prepared in moderate to good yields from 3-chloro-4-ethoxycarbonyl-5-aryl-6-methyl-3-pyridazine. All compounds synthesized were ineffective against Gram+, Gram- bacteria and fungi while 7e and 7j exhibited a fairly good activity against Trichomonas vaginalis.

Cyclopentenyl ethylamines active on CNS.

Two new cyclopentenylethylamines were prepared and were submitted to a pharmacological screening together with some others previously described and now reprepared. All compounds exhibited different degrees of depressive activity on CNS and good analgesic activity. Compound 5, bearing a phenyl group on the carbon atom to which the amino group is connected, appears rather interesting being the most active as analgesic and the least toxic. Compounds 2 and 3 are able to antagonize in a certain degree lethal doses of physostigmine and also, respectively, of pentylenetetrazole and strychnine.

Synthesis and pharmacological activity of 4-carbamoyl-6-beta-thienyl-4,5-dihydropyridazin-3-(2H)ones.

A new series of 4-carbamoyl-6-beta-thienyl-4,5-dihydropyridazin-3-(2H)ones 4a-g have been synthesized and tested for their anti-inflammatory and analgesic properties. Among the tested compounds, only 4f at 1 mmole/Kg showed antiinflammatory activity that was comparable with that of indomethacin (5 mg/Kg) though of shorter duration. Compounds 4a, 4e and especially 4g at 0.2 mmoles/Kg displayed relevant analgesic activity, 4g being the most potent derivative in the writhing test. Compounds 4c and 4g were found to possess analgesic activity also in the hot plate test.

[1,4-Disubstituted 1,3-dihydro-2H-1,5-benzo- and chlorobenzodiazepin-2-ones with activity on the central nervous system]. / 1,3-diidro-2H-1,5-benzo- e -clorobenzodiazepin-2-oni-1,4-disostituiti ad attività sul S.N.C.

In pursuing the study on pyridodiazepinone derivatives, in order to verify the variation of biological activity induced by replacement of the heteroaromatic with an aromatic nucleus and by the introduction of chlorine on the benzene ring, a series of 1-[(dialkylamino)alkyl]-4-phenyl-1,3-dihydro-2H-1,4-benzodiazepin- 2-ones and of 7-chloro-analogues were prepared. Some benzodiazepinones and their 7-chloro-analagous were subjected to pharmacological experimentation in order to evaluate and compare their effect upon mice with regard to exploratory activity, motor coordination and spontaneous motility. In addition their anti-strychnine, anti-cardiazole, anti-amphetamine and anti-reserpine activities were also evaluated.

Evaluation of alginate compressed matrices as prolonged drug delivery systems.

This research investigated the use of sodium alginate for the preparation of hydrophylic matrix tablets intended for prolonged drug release using ketoprofen as a model drug. The matrix tablets were prepared by direct compression using sodium alginate, calcium gluconate, and hydroxypropylmethylcellulose (HPMC) in different combinations and ratios. In vitro release tests and erosion studies of the matrix tablets were carried out in USP phosphate buffer (pH 7.4). Matrices consisting of sodium alginate alone or in combination with 10% and 20% of HPMC give a prolonged drug release at a fairly constant rate. Incorporation of different ratios of calcium gluconate leads to an enhancement of the release rate from the matrices and to the loss of the constant release rate of the drug. Only the matrices containing the highest quantity of HPMC (20%) maintained their capacity to release ketoprofen for a prolonged time.

[The possible use of a ready-to-us film system for microbiological control in drug preparation]. / Possibilità di utilizzo di un sistema a film reidratabile nel controllo microbiologico di preparati farmaceutici.

Aim of this work was to verify the possibility of using a ready-to-use plate-count method to detect the microbial and fungal contamination on pharmaceutical products. The system consists of a flexible polypropylene film, supporting a suitable dehydrated medium, a second support containing guar, and an indicator on the internal surface. 33 raw materials, 11 natural origin materials, 20 medicinal product of official formula and 18 homeopathic products were analysed. As reference we chose the Italian Pharmacopoeia method. The two methods were comparable, showing no statistical differences, but for one case. This method, if our date will be further confirmed, could be used by the pharmacies and by the homeopathic industries.

Cyclopenta[e] [1,5] benzodiazepin-10 (9H)-one derivatives as CNS depressant agents.

A series of dialkylaminoalkyl derivatives of cyclopenta[e] [1,5] benzodiazepin-10(9H)-one (E1-4) and its 6-chloro derivative (E5-8) was prepared to evaluate their CNS activity in comparison with that of isosteric pyridodiazepinones (A1-4) previously described. The results of the pharmacological screening show a significant depressant activity more remarkable in 6-chloro derivatives, which also revealed a high and lasting analgesic activity. The replacement of pyridine with benzene nucleus did not show any significant or homogeneous activity variation.

2,6-dialkylpiperazines. VII-Synthesis of N4-(2'-pyridyl)-2,6-dimethylpiperazine and separation of its geometrical isomers.

Cis-(I a) and trans-(I b) N4-(2'-pyridyl)-2,6-dimethylpiperazine were synthetised as the key intermediates for isomeric 2,6-dimethylpiperazine derivatives to be pharmacologically tested.

2,6-dialkylpiperazines. VIII (1)-N1-arylalkyl-N4-(2'-pyridyl)-2,6-dimethylpiperazines as adrenolytic and vasodilator agents.

A series of cis and trans N1-arylalkyl-N4-(2'-pyridyl)-2'6-dimethylpiperazines were synthetized and tested as adrenolytic and vasodilator agents. The N1-substitution with the 3,4-dimethoxyphenethyl group seems the most promising with regard to pharmacological activity, which was found to reside mainly in the trans isomer (3-II b). The adrenolytic activity of (3-II b) is comparable with that of the related 2-methyl derivative (1-III), while it is higher than that of (IV) in which the piperazine nucleus is C-unsubstituted.

Pyridazine N-oxides. III. Synthesis and "in vitro" antimicrobial properties of N-oxide derivatives based on tricyclic indeno[2,1-c]pyridazine and benzo[f]cinnoline systems.

A number of 9H-indeno[2,1-c]pyridazine N-oxides (3a-c) and benzo[f]cinnoline N-oxides (4,5a-c) have been synthesized and tested for antimicrobial activity. All new products were inactive against Gram negative bacteria and fungi. In contrast, among the compounds synthesized, 3b, 4b and 5b showed a moderate activity against Gram positive Staphylococcus aureus and Staphylococcus epidermidis. Of the present series, the 9-nitro-benzo[f]cinnoline N-oxide 5b possessed the highest activity especially against Trichomonas vaginalis (MIC = 3.9 micrograms/ml).

[Tert-aminoalkyl derivatives of quinoxalinones, aza- and diazaquinoxalinones with analgesic activity]. / Terz-amminoalchilderivati di chinossalinoni, aza e diazachinossalinoni ad attività analgesica.

A series of tert-aminoalkyl-derivatives of quinoxalin-2-one, aza- and diazaquinoxalin-2-one bearing in position 3 a benzyl group was prepared in order to compare with analogous 3-methyl derivatives as regards analgesic activity. The substitution causes various effects. In compounds (I) and (VI-IX) is found the expected increase in analgesic activity but with contemporaneous rise in toxicity. The compounds (IV) and (V) are of interest due to the presence of a strong separation of DL50 from DE50.

[Preparation and pharmacologic activity of 1-dimethylaminopropyl-3-methyl-6-chlorquinoxaline-2(1H)-one]. / Preparazione ed attività farmacologica dell'1-dimetilamminopropil-3-metil-6-clorochinossalin-2(1H)-one.

In continuation of previous research 1-dimetilaminopropyl-3-methyl-6-chlorquinoxaline-2(1H)-one was prepared. This compound shows affects on conditioned avoidance response together with analgesic action and inhibition of explorative activity, while it induces only a small degree of motor incoordination and does not protect the animals from toxic doses of strychinine and physostigmine.

[Pharmacologic activity of tert-aminoalkyl derivates of quinoxalinone, aza- and diaza-quinoxalinone]. / Attività farmacologica di terz-amminoalchilderivati di chinossalinoni aza- e diaza-chinossalinoni.

Eight tert-aminoalkyl derivatives of 3-methyl-6R-quinoxalin-2-one, 3-methyl-6/8-azaquinoxalin-2-ones and 3-methyl-6,8-diazaquinoxalin-2-one, previously selected for their deconditioning activity in rats were now tested in mice for analgesic, explorative and incoordinating (muscle relaxant) activities; acute toxicity was also determined. Several compounds show a good degree of activity in the tests used.