Non-peptide ligands for opioid receptors. Design of kappa-specific agonists.

A series of phenyl carboxyl esters 5a-d derived from N-(cyclopropylmethyl)normetazocine was synthesized and evaluated for its selectivity at mu, kappa, and delta opioid receptors. Compound 5a, although 43 times less potent than the reference compound U50488, was specific for kappa receptors, having no detectable affinity for either mu or delta receptors. Greater binding affinity was seen with the diastereoisomer having the 1'R,2'S stereochemistry in the cyclopropyl ring of the nitrogen substituent, which was only 12 times less active than U50488. Antinociceptive activity in the mouse tail flick was only slightly lower than that of U50488 (ED50 = 7.66 vs 4.52 mg/kg). Naloxone fully prevented antinociception induced by (1'R,2'S)-5a at the doses of 2.0 mg/kg. Compound (1'R,2'S)-5a is one of the most kappa-selective non-peptide compounds reported to date. The implications of these results in terms of requirements for kappa ligands are discussed.

(+)-cis-N-ethyleneamino-N-normetazocine derivatives. Novel and selective sigma ligands with antagonist properties.

A series of (+)-cis-N-normetazocine derivatives has been described, and their affinities for sigma1, sigma2, and phencyclidine (PCP) sites and opioid, muscarinic (M2), dopamine (D2), and serotonin (5-HT2) receptors were evaluated. The effect of the N-substitution with a substituted ethylamino spacer was investigated. Compounds 8c-11c displayed high affinities for sigma1 sites and for opioid receptors. Substitution of the second basic nitrogen either with alkyl or cycloalkyl substituents give compounds (1a-6a) with high affinity and selectivity for sigma1 binding sites. Compounds 1a-5a were further characterized in vivo, and their agonist/antagonist activity was evaluated. In mouse, compound 1a and 2a as well as haloperidol suppressed in a dose-related manner the stereotyped behavior induced by (+)-SKF 10,047. Compounds 3a-5a and (+)-pentazocine do not affect the stereotyped behavior induced by ip injection of (+)-SKF 10,047. Therefore, from this series of compounds we identified potent and selective sigma1 ligands which might prove useful to unveil the functional role of sigma1 sites.

Berberis aetnensis C. Presl. extracts: antimicrobial properties and interaction with ciprofloxacin.

Previous research showed that berberine-containing Berberis species synthesise the substances 5'-methoxyhydnocarpin-D (5'-MHC-D) and pheophorbide a, which have no antimicrobial activity but inhibit the expression of multidrug resistant efflux pumps (MDRs) in Staphylococcus aureus and potentiate the action of berberine. The MDR pumps extrude synthetic and natural antimicrobials from bacterial cells. We searched for these compounds in Berberis aetnensis C. Presl. (Berberidaceae), an endemic plant of the volcano Mount Etna. This work confirms the presence of pheophorbide a and permits us to hypothesise the presence of 5'-MHC-D in leaf extracts. In fact, the activity of ciprofloxacin was improved when two chromatographic fractions isolated from leaf extracts were added. These results are indicative of the presence of MDR pump inhibitors. Moreover, crude extracts were tested on several micro-organisms and showed antimicrobial activity mainly against Gram-positive bacteria and yeasts.

Chemical and pharmacological investigations on 2H-pyridazino[4,5-b] [1,4]benzothiazin-1(10H)-one derivatives.

The methylation of 2H-pyridazino [4,5-b][1,4]benzothiazin-1(10H)-one-5,5-dioxide 2 and the oxidation of 2-methyl-2H-pyridazino[4,5-b][1,4]benzothiazin-1(10H)-one 3 produced the same compound 4. On the contrary, in the 2-dialkylaminoalkylic series, the dialkylamino-alkylation and the oxidation reactions, carried out on compounds 2 and 8 respectively, afforded derivatives 7 and 9. In addition, the behaviour to the oxidation of the corresponding 10-methyl and 10-dialkylaminoalkyl analogues is also described. The synthesized compounds were tested for their analgesic, antiexudative and anti-inflammatory activities. The pharmacological results showed that in general dialkylaminoalkyl derivatives are more active than methyl derivatives. In particular, compounds 7 b, 9 b and 11 c exhibited an analgesic activity comparable to that of phenylbutazone; moreover 10-substituted compounds 11 a, 11 b and 11 c, screened p.o. as anti-inflammatory agents in rats, resulted equipotent to phenylbutazone and more active than 2-substituted isomers. These activities are coupled with a high LD50 and a very low ulcerogenic potential.

Synthesis and pharmacological evaluation of 3H-pyridazino[4,5-b][1,4]benzothiazin-4(10H)-one derivatives.

The dialkylamino-alkylation of 3H-pyridazino[4,5-b][1,4]benzothiazin-4(10H)-one-5,5-dioxide 5 produced the 3-dialkylaminoalkyl-derivatives 6. To the same compounds we arrived by selective reduction of the corresponding N-oxides 4, derived from the oxidation of the 3-dialkylaminoalkyl-3H-pyridazino[4,5-b][1,4]benzothiazin-4( 10H)-ones 3. Similarly, the oxidation of the 10-dialkylaminoalkyl analogues 8 afforded the corresponding derivatives 9. The synthesized compounds were tested, as hydrochlorides, for their analgesic and anti-inflammatory activities. The results showed that many of these compounds possess a very good analgesic activity, superior to that of phenylbutazone, apparently not related to the position and the peculiarities of the aminoalkylic side-chain. The anti-inflammatory activity was moderate, comparable only for 4 c to that of phenylbutazone. In the most active compounds a very low ulcerogenic potential and a high LD50 have been observed.

Synthesis of substituted pyrimidines, pyrazole[3,4-d]pyrimidines and imidazo[4,5-d]pyrimidines and evaluation of their antifungal activity.

Some pyrimidines, pyrazolo[3,4-d]pyrimidines and imidazo[4,5-d]pyrimidines bearing the 5-nitro- and 5-aminothienyl-2-sulfide functionalities on the pyrimidine nucleus were synthesized and evaluated for their antifungal activity against several strains of yeasts and dermatophytes. 4-Amino-2-pyrimidinyl-5'-nitro-2'-thienylsulfide (Va) resulted active against both yeasts and dermatophytes (about 30 fold less potent than Miconazole). Compds. (II b), (V b) and (VIII b) showed only a slight activity against dermatophytes, while the other compounds were inactive.

Synthesis of (+)-(1'R,2'S) and (1'S,2'R)-6,11-dimethyl-1,2,3,4,5,6 -hexahydro-3-[[2'-(alkoxycarbonyl)-2'-phenylcyclopropyl]methyl]-2 ,6 -methano-3-benzazocin-8-ol. Comparison of the affinities for sigma 1 and opioid receptors with in the diastereoisomeric MPCB and CCB.

The synthesis and the in vitro receptor affinity for sigma 1 and opiod receptors of the two diastereoisomers of (+)-cis-MPCB namely, (+)-cis-(1'S,2'R)-6,11-Dimethyl-1,2,3,4,5,6 -hexahydro-3-[[2'-(methoxycarbonyl)-2'-phenylcyclopropyl]methyl]-2 ,6 -methano-3-benzazocin-8-ol, (1'S,2'R)6a and (+)-cis-(1'R,2'S)-6,11-Dimethyl-1,2,3,4,5,6-hexahydro-3- [[2-(methoxycarbonyl)-2'-phenylcyclopropyl]methyl]-2,6-methano-3-+ ++benzazocin-8 -ol, (1'R,2'S)6a are reported. Affinities of (1'S,2'R)6a and (1'R,2'S)6a were compared with those of the (-)-cis-diastereoisomers of MPCB(1), and of its p-Cl phenyl derivative CCB(2). The (+)-cis-N-normetazocine derivatives showed higher affinity for the sigma 1 sites, labeled with [3H]-(+)-pentazocine than the corresponding (-)-cis- analogs. In particular, compound (1'S,2'R)6a showed a Ki = 66.7 nM for sigma 1 receptor, associated with a good selectivity for sigma 1 with respect to kappa, mu, delta opioid receptors subtypes (Ki = > 1,000 nM). Analysis of the data seem to support the hypothesis that the (+)-cis-N-normetazocine nucleus posses a specific enantioselectivity for sigma 1 sites, when supporting bulkier N-substituents functionalized with a carboxy ester group.

Studies on isoquinoline derivatives. IV. Synthesis and evaluation of the antimicrobial and antifungal activities of N2-arylidene-substituted 3-carbazoyl-isoquinolines.

2,4-Dimethyl-1-oxo-1,2-dihydro-3-carbazoyl-isoquinoline (II), 1-chloro-, 1-methoxy-3-carbazoyl-4-methylisoquinoline (VI, X) and a series of their hydrazonic derivatives have been synthesized and tested in vitro for antibacterial and antifungal activities. 1-(1-Chloro-4-methyl-3-isoquinolinoyl)-2-(5-nitro-2-furfurylide ne) hydrazine (VII h) proved to be the most effective in the series (MIC 0.78 micrograms/ml) and was more potent than furazolidone against several strains of S.aureus; the same compound also showed a moderate antifungal activity.

Synthesis and antibacterial activity of 3-(2-arylvinylen)-2-isoxazolines.

3-[2-(5-Nitro-2-furyl)vinylen]-2-isoxazoline (VIII) and 3-nitro-, 3-amino- and 3-acylaminostyryl-2-isoxazolines have been synthesized and tested for antibacterial activity. Compound (VIII) showed potent antibacterial activity in vitro against several strains of S. aureus and E. coli (two to eight times more active than furazolidone). None of the styryl derivatives exhibited significant activity.

Synthesis and biological activity of some di(nitrothienyl)- and di(acetylaminothienyl)sulfones.

Some new di(nitrothienyl)- and di(acetylaminothienyl)sulfones were synthesized. Compounds (I)-(VI) were active against several Gram-positive bacteria, in vitro. Di(5-acetylamino-2-thienyl)sulfone (VII) showed a mild antimalarial activity against a drug-sensitive strain of P. berghei in mice.

[Prospective study of HBV circulation and long-term evaluation of anti-hepatitis-B vaccination in patients undergoing hemodialysis]. / Studio prospettico sulla circolazione di HBV e valutazione a lungo termine della vaccinazione anti-epatite B in pazienti in emodialisi.

Hemodialysis patients were screened and monitored for HBV markers and at renal unit (identification EDTA 13ND) Palermo. Eighty-five patients received the hepatitis B vaccine (Haevac B Pasteur); fifty-three were followed up for more than three years; they received one of the three following schedules: 5 micrograms at 0, 1, 2 and 14 months; 5 micrograms at 0, 1, 2, 3, and 14 or 10 micrograms at 0, 1, 2, and 14 months. The best result was obtained by third schedule with a sero-conversion to anti-HBs of 83% at one month after the booster doses; and with the same percentage of anti-HBs positivity two years after the booster dose. During the study time (January 1984, March 1989) no new HBV events in patients and in the hemodialysis staff, who was also on monitoring, were observed.

[Synthesis and antifungal activity of new derivatives of 5-(4-halobenzoyl)-4-amino-3-(2-dialkylaminoethylthio)thieno [2,3-c] and [3,2-d] isothiazole]. / Sintesi ed attività antifungina di nuovi derivati 5-(4-alobenzoil)-4-ammino-3-(2-dialchilamminoetiltio)tieno [2,3-c] e [3,2-b] isotiazolici.

A new series of 5-(4-halobenzoyl)-4-amino-3-(2-dialkylamino-ethylthio)thieno [2,3-c] and [3,2-d] isothiazole derivatives has been synthetized. The compounds were evaluated for antifungal activity on yeast and dermatophytes. The compound (VI b) resulted about thirty times less potent than miconazole on dermatophytes.

[Synthesis of 2-methoxynaphthalene derivatives as potential anti-inflammatory agents]. / Sintesi di derivati della 2-metossinaftalina come potenziali antiinfiammatori.

Compounds having 2-methoxynaphthalene as their parent nucleus were synthesized and evaluated for antiinflammatory effect according to the carrageenin paw edema method in rats. The synthetic routes for the preparation of isomeric 1,2- and 2,6-disubstituted derivatives are described. Replacement of the alpha-methylacetic moiety in naproxen by 4-hydroxybutyric acid side chain did not cause loss of activity.