Maurizio Manfrini

Pyrazolo-triazoles as light activable dna cleaving agents

In view of the continuous interest in new DNA cleaving compounds, both for the development of new therapeutic agents and for the possible use as reagents in nucleic acids research, a few pyrazolo[3,4-d][1,2,3]triazole derivatives have been obtained and investigated for their antiproliferative activity and capability to cleave DNA, after light-activation. A possible in situ activation, i.e. in neoplastic tissues, of less cytotoxic derivatives, may lead to potential antitumor compounds endowed with high therapeutic indexes.

Antifungal activity of 5 new synthetic compounds vs. Trichophyton rubrum and Epidermophyton floccosum.

The antifungal activity of five new synthetic compounds was evaluated on two dermatophytes: Epidermophyton floccosum and Trichophyton rubrum. The data showed that the imidazo-pyrazole and pyrazolo-thiazoles were not particularly effective, while the two pyrazole-thiocyanates proved highly active on both fungi. The most active 5-amino-3-methyl-1-phenylpyrazolo-4-thiocyanate was chosen to perform SEM and TEM morphological studies on both fungi. Both SEM and TEM observations revealed interesting alterations on the two dermatophytes, particularly involving the endomembrane system.

Synthesis of a novel series of imidazo[4,5-c]pyrazole derivatives and their evaluation as herbicidal agents

Ever changing problems in agricultural weed control require periodic introduction of new herbicides. Imidazo[4,5‐c]pyrazoles, which were considered of interest as potential herbicides, were synthesized and examined for the pre‐emergence, post‐emergence, and post‐transplant control of weeds in rice against broadleaf and grass weed species. The data obtained suggest that some imidazo[4,5‐c]pyrazoles have potential herbicidal activity against a wide range of weeds, with 5‐methyl, 5‐thiomethyl, and 5‐unsubstituted derivatives being the most effective. No herbicidal activity was observed in the 5‐methylsulfonylimidazo[4,5‐c]pyrazole and imidazo[4,5‐c]pyrazolone series.

Synthesis and biological evaluation of a series of substituted pyrazolo[3,4-d]-1,2,3-triazoles and pyrazolo[3,4-d]oxazoles.

In view of the biological relevance of triazole‐based heterocyclic structures as antifungal, antiviral, and antitumor agents, we have synthesized a series of substituted pyrazolo[3,4‐d]‐1,2,3‐triazoles (2e–h, 2j, 4b) which we evaluated for their cytostatic and antiviral (HIV‐1 included) activity and for their capability to inhibit the multiplication of various human pathogenic fungi and bacteria. Moreover, the biological activities of a few compounds, namely pyrazolo[3,4‐d]oxazoles (3a–e) and pyrazolo[3,4‐d]‐1,2,3‐triazoles (2a–d, 4a, 5), previously obtained by us but not investigated for their biological activity, were also studied. Only compounds 3a–e were endowed with a significative antiproliferative activity on the human lymphoblastoid cell line MT‐4 cells. All pyrazole derivatives proved ineffective in protecting cell cultures against the HIV‐1‐induced cytopathogenicity, and none of the compounds was active against the bacteria and fungi tested.

An Efficient Procedure for the Synthesis of Pyrazolo]3,4-d][1,3]thiazine-4-ones

Trichloromethyl chloroformate reacts with N-(1-alkyl/aryl-5-pyrazolyl) thiocarboxamides (2a-j) to give pyrazolo[3,4-d][1,3]thiazin-4-ones (3) while it reacts with N-(3-methyl-5-pyrazolyl)thiobenzamide (2m) to give the pyrazolo[1,5-c] [1,3,5]thiadiazine-4-one (4). Heating under reflux in formic acid of homologues (3g-i) bearing a tert-butyl group linked to pyrazole N-1 atom afforded the dealkylated derivatives (3k-m)

Imidazo[4,5-c]pyrazoles synthesis of 4-,5- and 6-substituted derivatives

Abstract The syntheses of 4-, 5-, and 6- substituted imidazo[4,5-c]pyrazoles, compounds of potential biological activity, are reported.

A New Synthesis of Pyrazolo[3,4-d]thiazoles

An efficient synthesis of pyrazolo[3,4-d]thiazoles (6) was achieved by treatment of N-(4-amino-5-pyrazolyl)thiocarboxamides (4) with sodium nitrite in acidic medium followed by irradiation with uv light