Daniele Pezzetta - Academia.edu (original) (raw)
Papers by Daniele Pezzetta
Molecular Pharmaceutics, 2006
Multidrug resistance mediated by ATP binding cassette (ABC) transporters such as P-glycoprotein (... more Multidrug resistance mediated by ATP binding cassette (ABC) transporters such as P-glycoprotein (P-gp) represents a serious problem for the development of effective anticancer drugs. In addition, P-gp has been shown to reduce oral absorption, modulate hepatic, renal, or intestinal elimination, and restrict blood-brain barrier penetration of several drugs. Consequently, there is a great interest in anticipating whether drug candidates are P-gp substrates or inhibitors. In this respect, two different computational models have been developed. A method for discriminating P-gp substrates and nonsubstrates has been set up based on calculated molecular descriptors and multivariate analysis using a training set of 53 diverse drugs. These compounds were previously classified as P-gp substrates or nonsubstrates on the basis of the efflux ratio from Caco-2 permeability measurements. The program Volsurf was used to compute the compounds' molecular descriptors. The descriptors were correlated to the experimental classes using partial least squares discriminant analysis (PLSD). The model was able to predict correctly the behavior of 72% of an external set of 272 proprietary compounds. Thirty of the 53 previously mentioned drugs were also evaluated for P-gp inhibition using a calcein-AM (CAM) assay. On the basis of these additional P-gp functional data, a PLSD analysis using GRIND-pharmacophorebased descriptors was performed to model P-gp substrates having poor or no inhibitory activity versus inhibitors having no evidence of significant transport. The model was able to discriminate between 69 substrates and 56 inhibitors taken from the literature with an average accuracy of 82%. The model allowed also the identification of some key molecular features that differentiate a substrate from an inhibitor, which should be taken into consideration in the design of new candidate drugs. These two models can be implemented in a virtual screening funnel.
Toxicology in Vitro, 2004
Martignoni, M. (2006). Species and strain differences in drug metabolism in liver and intestine. ... more Martignoni, M. (2006). Species and strain differences in drug metabolism in liver and intestine. s.n.
Journal of Medicinal Chemistry, 2009
Arzneimittelforschung, 2011
The seven O-methylated analogs of dobutamine [(+/-)-4-[2-[[3-(p-hydroxyphenyl)-1-methylpropyl]ami... more The seven O-methylated analogs of dobutamine [(+/-)-4-[2-[[3-(p-hydroxyphenyl)-1-methylpropyl]amino]ethyl]pyrocatechol, CAS 34368-04-2), a trihydroxy secondary amine, can be considered potential impurities of the latter, the ultimate step of the synthesis of dobutamine being the deprotection of the three phenolic groups. In order to enable the detection and the identification of such a contamination, the di- and the monomethylated derivatives of dobutamine were prepared and their mixture with dobutamine and its trimethoxy precursor completely resolved by Free Solution Capillary Electrophoresis (FSCE). Indeed, the above impurities proved to occur in dobutamine in consequence of improper demethylation conditions and to be significantly more toxic than the latter.
Bioorganic & Medicinal Chemistry Letters, 2010
A series of 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives was optimized as Polo-like kina... more A series of 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives was optimized as Polo-like kinase 1 inhibitors. Extensive SAR afforded a highly potent and selective PLK1 compound. The compound showed good antiproliferative activity when tested in a panel of tumor cell lines with PLK1 related mechanism of action and with good in vivo antitumor efficacy in two xenograft models after i.v. administration.
A224 The Cell Division Cycle 7 (Cdc7) kinase plays a pivotal role in regulating DNA replication i... more A224 The Cell Division Cycle 7 (Cdc7) kinase plays a pivotal role in regulating DNA replication in eukaryotic organisms. Inhibition of Cdc7 kinase by both siRNAs and small molecule inhibitors (Montagnoli et al.,2007 AACR Annual Meeting, April 14-18 2007, Los Angeles, CA) causes p53 independent tumor cell death, while it only causes reversible cell cycle arrest in primary fibroblasts supporting the rationale for the development of Cdc7 kinase inhibitors as antitumor agents. Starting from 2-pyridin-4-yl-1,5,6,7-tetrahydro-pyrrolo[3,2-c]pyridin-4-one 1a (IC50 = 10 nM in a Cdc7/Dbf4 kinase assay and greater than 20-fold selectivity vs a panel of other kinases), a strictly related analog 1b was obtained and also proved to be a promising scaffold for Cdc7 inhibition (IC50 = 7 nM in a Cdc7/Dbf4 kinase assay and greater than 40-fold selectivity vs a panel of other kinases). In this poster we present the synthesis, structure-activity relationships (SAR) investigation, and biological data of analogues derived from the two compounds 1a and 1b. In particular the SAR studies revealed that position 7 of both compounds could be profitably substituted to yield potent Cdc7 inhibitors. Among those compounds, derivative 8b (S) inhibited Cdc7/Dbf4 kinase with IC50 = 2 nM with greater than 60-fold selectivity vs a panel of kinases, and hampered tumor cell proliferation of different cell lines with an IC50 in the submicromolar range. 24h treatment of A2780 ovary carcinoma cells with cpd 8b (S) induced inhibition of Ser40-Mcm2 phosphorylation and apoptosis. Due to its favourable PK profile, the antitumor activity of this compound was evaluated in a A2780 xenograft model by oral administration (60mg/Kg bid, 10d) yielding a TGI = 68% with evidences of target inhibition in tumors. Finally in DMBA induced mammary carcinoma in rats, compound 8b (S) orally administered (20mg/kg bid, 10d) displayed durable tumor stabilisation.
![Research paper thumbnail of NMS-P937, a 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivative as potent and selective Polo-like kinase 1 inhibitor](https://attachments.academia-assets.com/86172681/thumbnails/1.jpg)
](Bioorganic & Medicinal Chemistry Letters, 2011
Ejc Suppl, 2010
Poster Session-DNA repair and inhibitors phosphorylation of the Hsp90 co-chaperone, Cdc37 at the ... more Poster Session-DNA repair and inhibitors phosphorylation of the Hsp90 co-chaperone, Cdc37 at the CK2-specific Ser13 site that was accompanied by a reduction in levels of Chk1. Upon combination with gemcitabine, CX-4945 down regulated the expression of Mcl-1 and survivin, two anti-apoptotic proteins known to regulate sensitivity to gemcitabine. CX-4945 + gemcitabine administered to A2780 xenografts was well tolerated, showed an increase in PARP cleavage and significantly enhanced the antitumor activity compared to gemcitabine alone (6/10 regressions versus no regressions). Conclusions: Inhibition of CK2 by CX-4945 enhances the antitumor activity of gemcitabine by disrupting DNA damage repair and down regulating anti-apoptotic mediators. These data provide preclinical support for combining CX-4945 with gemcitabine in solid tumors. 519 POSTER Are the methylation of MGMT (O6-methylguanine-DNA methyltransferase) and the DNA mismatch repair (MMR) mechanism frequently involved in pediatric cancers?
![Research paper thumbnail of Synthesis of Homochiral 5- and 8- Substituted 2-[((2-(2,6-Dimethoxyphenoxy)- ethyl)amino)methyl]-1,4-benzodioxanes and Electrophoretic Determination of Their Enantiomeric Excess](https://attachments.academia-assets.com/72716152/thumbnails/1.jpg)
](The Journal of Organic Chemistry, Jan 5, 2001
24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic func... more 24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic function of (R)-9 and (R)-16; (g) amination with 2-(2,6-dimethoxyphenoxy)ethylamine. The R enantiomers of 1-3 were synthesized by the same strategy as illustrated in Scheme 1 but starting from the tosyl ester of (R)-glycerol acetonide [(S)-4]. 2-(Benzyloxy)-3-fluorophenol used in the first step of the syntesis of (S)-3 and (R)-3 was prepared from 2-fluorophenol as outlined in Scheme 3. Esterification with acetyl chloride, followed by Fries rearrangement and benzylation of the resulting hydroxyketone 26, afforded 2-(benzyloxy)-3-fluoroacetophenone (27), which was converted into the corresponding phenyl acetate 28 by the Baeyer-Villiger reaction and finally submitted to methanolysis. The enantiomeric purity of the optical isomers of WB4101 and of its three novel analogues was initially investigated by applying chromatographic methods. However, their previous conversion into diastereomeric amides by reaction with optically pure R-methoxy-R-(trifluoromethyl)phenylacetyl chloride was required to obtain analytical HPLC separation, while attempts at direct resolution of the enantiomers by HPLC on chiral station-Scheme 2 Scheme 3 Notes
European Journal of Pharmaceutical Sciences, Nov 30, 2007
Solubility is one of the most important properties of drug candidates for achieving the targeted ... more Solubility is one of the most important properties of drug candidates for achieving the targeted plasma concentrations following oral dosing. Furthermore, the formulations adopted in the in vivo preclinical studies, for both oral and intravenous administrations, are usually solutions. To formulate compounds sparingly soluble in water, pharmaceutically acceptable cosolvents or surfactants are typically employed to increase solubility. Compounds poorly soluble also in these systems will likely show severe formulation issues. In such cases, relatively high amount of compounds, rarely available in the early preclinical phases, are needed to identify the most appropriate dosing vehicles. Hence, the purpose of this study was to build two computational models which, on the basis of the molecular structure, are able to predict the compound solubility in two vehicle systems (40% PEG400/water and 10% Tween80/water) used in our company as screening tools for anticipating potential formulation issues. The two models were developed using the solubility data obtained from the analysis of approximately 2000 chemically diverse compounds. The structural diversity and the drug-like space covered by these molecules were investigated using the ChemGPS methodology. The compounds were classified (high/low preformulation risk) based on the experimental solubility value range. A combination of descriptors (i.e. log D at two different pH, Estate indices and other 2D structural descriptors) was correlated to these classes using partial least squares discriminant (PLSD) analysis. The overall accuracy of each PLSD model applied to independent sets of compounds was approximately 78%. The accuracy reached when the models were used in combination to identify molecules with low preformulation risk in both systems was 83%. The models appeared a valuable tool for predicting the preformulation risk of drug candidates and consequently for identifying the most appropriate dosing vehicles to be further investigated before the first in vivo preclinical studies. Since only a small number of 2D descriptors is need to evaluate the preformulation risk classes, the models resulted easy to use and characterized by high throughput.
Midazolam and testosterone are CYP3A4 substrates commonly used for in vitro investigations into d... more Midazolam and testosterone are CYP3A4 substrates commonly used for in vitro investigations into drug metabolism and drug-drug interactions. In order to assess their potential interaction at the active site of CYP3A4, they were incubated, either individually or in combination, with a recombinant CYP3A4 expression system. The formation of the main metabolites of midazolam (1OH- and 4OH-Midazolam) and testosterone (6bOH- 16bOH-, 2aOH and 2bOH-Testosterone) was followed and the inhibitory effect of nineteen specific enzyme inhibitors was investigated (erytromicin, digitoxin, ketoconazole, itraconazole, astemizol, dextromethorphan, ibuprofen, quinidine, clotrimazole, verapamil, budesonide, terfenadine, clozapine, diltiazem, progesterone, tamoxifen, paclitaxel, cyclosporine and nifedipine). The IC50 values were similar after both individual and combined incubations. In addition, when midazolam and testosterone were incubated together, the rank order of IC50 values based on the formation o...
Journal of Medicinal Chemistry, 2015
The nuclear protein poly(ADP-ribose) polymerase-1 (PARP-1) has a well-established role in the sig... more The nuclear protein poly(ADP-ribose) polymerase-1 (PARP-1) has a well-established role in the signaling and repair of DNA and is a prominent target in oncology, as testified by the number of candidates in clinical testing that unselectively target both PARP-1 and its closest isoform PARP-2. The goal of our program was to find a PARP-1 selective inhibitor that would potentially mitigate toxicities arising from cross-inhibition of PARP-2. Thus, an HTS campaign on the proprietary Nerviano Medical Sciences (NMS) chemical collection, followed by SAR optimization, allowed us to discover 2-[1-(4,4-difluorocyclohexyl)piperidin-4-yl]-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxamide (NMS-P118, 20by). NMS-P118 proved to be a potent, orally available, and highly selective PARP-1 inhibitor endowed with excellent ADME and pharmacokinetic profiles and high efficacy in vivo both as a single agent and in combination with Temozolomide in MDA-MB-436 and Capan-1 xenograft models, respectively. Cocrystal structures of 20by with both PARP-1 and PARP-2 catalytic domain proteins allowed rationalization of the observed selectivity.
Understanding the biotransformation of a drug is a key activity at all stages of the research and... more Understanding the biotransformation of a drug is a key activity at all stages of the research and development process. In vitro metabolite profiling by liquid chromatography – mass spectrometry (MS) techniques at early discovery stages is useful to evaluate interspecies differences and determine possible unfavourable metabolism pathways. The gained knowledge is useful in the subsequent preclinical development stage where species comparison and in vitro – in vivo correlations are carried out. These activities received even more attention since the publications issued by the U.S. Food and Drug Administration (FDA, 2008) and the International Conference on Harmonization (ICH, 2009) on the safety testing of drug metabolites early in the drug development process of a candidate drug.In this poster we present a case study of in vitro and in vivo metabolism investigations showing significant differences among species. Metabolite profiling on plasma samples obtained after human dosing allowe...
Xenobiotica; the fate of foreign compounds in biological systems, Jan 3, 2015
1. The metabolism of CHF 6001, a novel PDE4 inhibitor, was determined in vitro in mouse, rat, dog... more 1. The metabolism of CHF 6001, a novel PDE4 inhibitor, was determined in vitro in mouse, rat, dog, monkey and human microsomes and hepatocytes and in vivo in plasma, urine, feces and bile of rats after intravenous and intratracheal administration. 2. The behavior of CHF 6001 in microsomes and hepatocytes changed across species. CYP3A4/5 isoenzymes were identified to be the primary enzymes responsible for the metabolism of CHF 6001 in human liver microsomes. 3. In the rat, CHF 6001 was found extensively metabolized in urine, feces and bile, but not in plasma, where CHF 6001 was the main compound present. The metabolite profiles were different in the four biological matrices from both qualitative and quantitative point of view. 4. CHF 6001 was metabolized through hydrolysis with the formation of the alcohol CHF 5956, loss of a chlorine atom, loss of the N-oxide, hydroxylation, loss of the cyclopropylmethyl group in the alcohol moiety, conjugation with glucuronic acid, glutathione and ...
![Research paper thumbnail of ChemInform Abstract: Synthesis of Homochiral 5- and 8-Substituted 2-[((2-(2,6-Dimethoxyphenoxy)ethyl)amino)methyl]-1,4-benzodioxanes and Electrophoretic Determination of Their Enantiomeric Excess](https://attachments.academia-assets.com/72716148/thumbnails/1.jpg)
](ChemInform, 2001
Synthesis of Homochiral 5-and 8-Substituted 2-[((2-(2,6-Dimethoxyphenoxy)ethyl)amino)methyl]-1,4-... more Synthesis of Homochiral 5-and 8-Substituted 2-[((2-(2,6-Dimethoxyphenoxy)ethyl)amino)methyl]-1,4-benzodioxanes and Electrophoretic Determination of Their Enantiomeric Excess.-Some title compounds like (VIII) and (XIV) are prepared in order to test their biological activity.
Rapid Communications in Mass Spectrometry, 2000
![Research paper thumbnail of Synthesis of Homochiral 5- and 8- Substituted 2-[((2-(2,6-Dimethoxyphenoxy)- ethyl)amino)methyl]-1,4-benzodioxanes and Electrophoretic Determination of Their Enantiomeric Excess](https://attachments.academia-assets.com/72716137/thumbnails/1.jpg)
](The Journal of Organic Chemistry, 2001
24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic func... more 24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic function of (R)-9 and (R)-16; (g) amination with 2-(2,6-dimethoxyphenoxy)ethylamine. The R enantiomers of 1-3 were synthesized by the same strategy as illustrated in Scheme 1 but starting from the tosyl ester of (R)-glycerol acetonide [(S)-4]. 2-(Benzyloxy)-3-fluorophenol used in the first step of the syntesis of (S)-3 and (R)-3 was prepared from 2-fluorophenol as outlined in Scheme 3. Esterification with acetyl chloride, followed by Fries rearrangement and benzylation of the resulting hydroxyketone 26, afforded 2-(benzyloxy)-3-fluoroacetophenone (27), which was converted into the corresponding phenyl acetate 28 by the Baeyer-Villiger reaction and finally submitted to methanolysis. The enantiomeric purity of the optical isomers of WB4101 and of its three novel analogues was initially investigated by applying chromatographic methods. However, their previous conversion into diastereomeric amides by reaction with optically pure R-methoxy-R-(trifluoromethyl)phenylacetyl chloride was required to obtain analytical HPLC separation, while attempts at direct resolution of the enantiomers by HPLC on chiral station-Scheme 2 Scheme 3 Notes
Molecular Pharmaceutics, 2006
Multidrug resistance mediated by ATP binding cassette (ABC) transporters such as P-glycoprotein (... more Multidrug resistance mediated by ATP binding cassette (ABC) transporters such as P-glycoprotein (P-gp) represents a serious problem for the development of effective anticancer drugs. In addition, P-gp has been shown to reduce oral absorption, modulate hepatic, renal, or intestinal elimination, and restrict blood-brain barrier penetration of several drugs. Consequently, there is a great interest in anticipating whether drug candidates are P-gp substrates or inhibitors. In this respect, two different computational models have been developed. A method for discriminating P-gp substrates and nonsubstrates has been set up based on calculated molecular descriptors and multivariate analysis using a training set of 53 diverse drugs. These compounds were previously classified as P-gp substrates or nonsubstrates on the basis of the efflux ratio from Caco-2 permeability measurements. The program Volsurf was used to compute the compounds' molecular descriptors. The descriptors were correlated to the experimental classes using partial least squares discriminant analysis (PLSD). The model was able to predict correctly the behavior of 72% of an external set of 272 proprietary compounds. Thirty of the 53 previously mentioned drugs were also evaluated for P-gp inhibition using a calcein-AM (CAM) assay. On the basis of these additional P-gp functional data, a PLSD analysis using GRIND-pharmacophorebased descriptors was performed to model P-gp substrates having poor or no inhibitory activity versus inhibitors having no evidence of significant transport. The model was able to discriminate between 69 substrates and 56 inhibitors taken from the literature with an average accuracy of 82%. The model allowed also the identification of some key molecular features that differentiate a substrate from an inhibitor, which should be taken into consideration in the design of new candidate drugs. These two models can be implemented in a virtual screening funnel.
Toxicology in Vitro, 2004
Martignoni, M. (2006). Species and strain differences in drug metabolism in liver and intestine. ... more Martignoni, M. (2006). Species and strain differences in drug metabolism in liver and intestine. s.n.
Journal of Medicinal Chemistry, 2009
Arzneimittelforschung, 2011
The seven O-methylated analogs of dobutamine [(+/-)-4-[2-[[3-(p-hydroxyphenyl)-1-methylpropyl]ami... more The seven O-methylated analogs of dobutamine [(+/-)-4-[2-[[3-(p-hydroxyphenyl)-1-methylpropyl]amino]ethyl]pyrocatechol, CAS 34368-04-2), a trihydroxy secondary amine, can be considered potential impurities of the latter, the ultimate step of the synthesis of dobutamine being the deprotection of the three phenolic groups. In order to enable the detection and the identification of such a contamination, the di- and the monomethylated derivatives of dobutamine were prepared and their mixture with dobutamine and its trimethoxy precursor completely resolved by Free Solution Capillary Electrophoresis (FSCE). Indeed, the above impurities proved to occur in dobutamine in consequence of improper demethylation conditions and to be significantly more toxic than the latter.
Bioorganic & Medicinal Chemistry Letters, 2010
A series of 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives was optimized as Polo-like kina... more A series of 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives was optimized as Polo-like kinase 1 inhibitors. Extensive SAR afforded a highly potent and selective PLK1 compound. The compound showed good antiproliferative activity when tested in a panel of tumor cell lines with PLK1 related mechanism of action and with good in vivo antitumor efficacy in two xenograft models after i.v. administration.
A224 The Cell Division Cycle 7 (Cdc7) kinase plays a pivotal role in regulating DNA replication i... more A224 The Cell Division Cycle 7 (Cdc7) kinase plays a pivotal role in regulating DNA replication in eukaryotic organisms. Inhibition of Cdc7 kinase by both siRNAs and small molecule inhibitors (Montagnoli et al.,2007 AACR Annual Meeting, April 14-18 2007, Los Angeles, CA) causes p53 independent tumor cell death, while it only causes reversible cell cycle arrest in primary fibroblasts supporting the rationale for the development of Cdc7 kinase inhibitors as antitumor agents. Starting from 2-pyridin-4-yl-1,5,6,7-tetrahydro-pyrrolo[3,2-c]pyridin-4-one 1a (IC50 = 10 nM in a Cdc7/Dbf4 kinase assay and greater than 20-fold selectivity vs a panel of other kinases), a strictly related analog 1b was obtained and also proved to be a promising scaffold for Cdc7 inhibition (IC50 = 7 nM in a Cdc7/Dbf4 kinase assay and greater than 40-fold selectivity vs a panel of other kinases). In this poster we present the synthesis, structure-activity relationships (SAR) investigation, and biological data of analogues derived from the two compounds 1a and 1b. In particular the SAR studies revealed that position 7 of both compounds could be profitably substituted to yield potent Cdc7 inhibitors. Among those compounds, derivative 8b (S) inhibited Cdc7/Dbf4 kinase with IC50 = 2 nM with greater than 60-fold selectivity vs a panel of kinases, and hampered tumor cell proliferation of different cell lines with an IC50 in the submicromolar range. 24h treatment of A2780 ovary carcinoma cells with cpd 8b (S) induced inhibition of Ser40-Mcm2 phosphorylation and apoptosis. Due to its favourable PK profile, the antitumor activity of this compound was evaluated in a A2780 xenograft model by oral administration (60mg/Kg bid, 10d) yielding a TGI = 68% with evidences of target inhibition in tumors. Finally in DMBA induced mammary carcinoma in rats, compound 8b (S) orally administered (20mg/kg bid, 10d) displayed durable tumor stabilisation.
Bioorganic & Medicinal Chemistry Letters, 2011
Ejc Suppl, 2010
Poster Session-DNA repair and inhibitors phosphorylation of the Hsp90 co-chaperone, Cdc37 at the ... more Poster Session-DNA repair and inhibitors phosphorylation of the Hsp90 co-chaperone, Cdc37 at the CK2-specific Ser13 site that was accompanied by a reduction in levels of Chk1. Upon combination with gemcitabine, CX-4945 down regulated the expression of Mcl-1 and survivin, two anti-apoptotic proteins known to regulate sensitivity to gemcitabine. CX-4945 + gemcitabine administered to A2780 xenografts was well tolerated, showed an increase in PARP cleavage and significantly enhanced the antitumor activity compared to gemcitabine alone (6/10 regressions versus no regressions). Conclusions: Inhibition of CK2 by CX-4945 enhances the antitumor activity of gemcitabine by disrupting DNA damage repair and down regulating anti-apoptotic mediators. These data provide preclinical support for combining CX-4945 with gemcitabine in solid tumors. 519 POSTER Are the methylation of MGMT (O6-methylguanine-DNA methyltransferase) and the DNA mismatch repair (MMR) mechanism frequently involved in pediatric cancers?
The Journal of Organic Chemistry, Jan 5, 2001
24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic func... more 24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic function of (R)-9 and (R)-16; (g) amination with 2-(2,6-dimethoxyphenoxy)ethylamine. The R enantiomers of 1-3 were synthesized by the same strategy as illustrated in Scheme 1 but starting from the tosyl ester of (R)-glycerol acetonide [(S)-4]. 2-(Benzyloxy)-3-fluorophenol used in the first step of the syntesis of (S)-3 and (R)-3 was prepared from 2-fluorophenol as outlined in Scheme 3. Esterification with acetyl chloride, followed by Fries rearrangement and benzylation of the resulting hydroxyketone 26, afforded 2-(benzyloxy)-3-fluoroacetophenone (27), which was converted into the corresponding phenyl acetate 28 by the Baeyer-Villiger reaction and finally submitted to methanolysis. The enantiomeric purity of the optical isomers of WB4101 and of its three novel analogues was initially investigated by applying chromatographic methods. However, their previous conversion into diastereomeric amides by reaction with optically pure R-methoxy-R-(trifluoromethyl)phenylacetyl chloride was required to obtain analytical HPLC separation, while attempts at direct resolution of the enantiomers by HPLC on chiral station-Scheme 2 Scheme 3 Notes
European Journal of Pharmaceutical Sciences, Nov 30, 2007
Solubility is one of the most important properties of drug candidates for achieving the targeted ... more Solubility is one of the most important properties of drug candidates for achieving the targeted plasma concentrations following oral dosing. Furthermore, the formulations adopted in the in vivo preclinical studies, for both oral and intravenous administrations, are usually solutions. To formulate compounds sparingly soluble in water, pharmaceutically acceptable cosolvents or surfactants are typically employed to increase solubility. Compounds poorly soluble also in these systems will likely show severe formulation issues. In such cases, relatively high amount of compounds, rarely available in the early preclinical phases, are needed to identify the most appropriate dosing vehicles. Hence, the purpose of this study was to build two computational models which, on the basis of the molecular structure, are able to predict the compound solubility in two vehicle systems (40% PEG400/water and 10% Tween80/water) used in our company as screening tools for anticipating potential formulation issues. The two models were developed using the solubility data obtained from the analysis of approximately 2000 chemically diverse compounds. The structural diversity and the drug-like space covered by these molecules were investigated using the ChemGPS methodology. The compounds were classified (high/low preformulation risk) based on the experimental solubility value range. A combination of descriptors (i.e. log D at two different pH, Estate indices and other 2D structural descriptors) was correlated to these classes using partial least squares discriminant (PLSD) analysis. The overall accuracy of each PLSD model applied to independent sets of compounds was approximately 78%. The accuracy reached when the models were used in combination to identify molecules with low preformulation risk in both systems was 83%. The models appeared a valuable tool for predicting the preformulation risk of drug candidates and consequently for identifying the most appropriate dosing vehicles to be further investigated before the first in vivo preclinical studies. Since only a small number of 2D descriptors is need to evaluate the preformulation risk classes, the models resulted easy to use and characterized by high throughput.
Midazolam and testosterone are CYP3A4 substrates commonly used for in vitro investigations into d... more Midazolam and testosterone are CYP3A4 substrates commonly used for in vitro investigations into drug metabolism and drug-drug interactions. In order to assess their potential interaction at the active site of CYP3A4, they were incubated, either individually or in combination, with a recombinant CYP3A4 expression system. The formation of the main metabolites of midazolam (1OH- and 4OH-Midazolam) and testosterone (6bOH- 16bOH-, 2aOH and 2bOH-Testosterone) was followed and the inhibitory effect of nineteen specific enzyme inhibitors was investigated (erytromicin, digitoxin, ketoconazole, itraconazole, astemizol, dextromethorphan, ibuprofen, quinidine, clotrimazole, verapamil, budesonide, terfenadine, clozapine, diltiazem, progesterone, tamoxifen, paclitaxel, cyclosporine and nifedipine). The IC50 values were similar after both individual and combined incubations. In addition, when midazolam and testosterone were incubated together, the rank order of IC50 values based on the formation o...
Journal of Medicinal Chemistry, 2015
The nuclear protein poly(ADP-ribose) polymerase-1 (PARP-1) has a well-established role in the sig... more The nuclear protein poly(ADP-ribose) polymerase-1 (PARP-1) has a well-established role in the signaling and repair of DNA and is a prominent target in oncology, as testified by the number of candidates in clinical testing that unselectively target both PARP-1 and its closest isoform PARP-2. The goal of our program was to find a PARP-1 selective inhibitor that would potentially mitigate toxicities arising from cross-inhibition of PARP-2. Thus, an HTS campaign on the proprietary Nerviano Medical Sciences (NMS) chemical collection, followed by SAR optimization, allowed us to discover 2-[1-(4,4-difluorocyclohexyl)piperidin-4-yl]-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxamide (NMS-P118, 20by). NMS-P118 proved to be a potent, orally available, and highly selective PARP-1 inhibitor endowed with excellent ADME and pharmacokinetic profiles and high efficacy in vivo both as a single agent and in combination with Temozolomide in MDA-MB-436 and Capan-1 xenograft models, respectively. Cocrystal structures of 20by with both PARP-1 and PARP-2 catalytic domain proteins allowed rationalization of the observed selectivity.
Understanding the biotransformation of a drug is a key activity at all stages of the research and... more Understanding the biotransformation of a drug is a key activity at all stages of the research and development process. In vitro metabolite profiling by liquid chromatography – mass spectrometry (MS) techniques at early discovery stages is useful to evaluate interspecies differences and determine possible unfavourable metabolism pathways. The gained knowledge is useful in the subsequent preclinical development stage where species comparison and in vitro – in vivo correlations are carried out. These activities received even more attention since the publications issued by the U.S. Food and Drug Administration (FDA, 2008) and the International Conference on Harmonization (ICH, 2009) on the safety testing of drug metabolites early in the drug development process of a candidate drug.In this poster we present a case study of in vitro and in vivo metabolism investigations showing significant differences among species. Metabolite profiling on plasma samples obtained after human dosing allowe...
Xenobiotica; the fate of foreign compounds in biological systems, Jan 3, 2015
1. The metabolism of CHF 6001, a novel PDE4 inhibitor, was determined in vitro in mouse, rat, dog... more 1. The metabolism of CHF 6001, a novel PDE4 inhibitor, was determined in vitro in mouse, rat, dog, monkey and human microsomes and hepatocytes and in vivo in plasma, urine, feces and bile of rats after intravenous and intratracheal administration. 2. The behavior of CHF 6001 in microsomes and hepatocytes changed across species. CYP3A4/5 isoenzymes were identified to be the primary enzymes responsible for the metabolism of CHF 6001 in human liver microsomes. 3. In the rat, CHF 6001 was found extensively metabolized in urine, feces and bile, but not in plasma, where CHF 6001 was the main compound present. The metabolite profiles were different in the four biological matrices from both qualitative and quantitative point of view. 4. CHF 6001 was metabolized through hydrolysis with the formation of the alcohol CHF 5956, loss of a chlorine atom, loss of the N-oxide, hydroxylation, loss of the cyclopropylmethyl group in the alcohol moiety, conjugation with glucuronic acid, glutathione and ...
ChemInform, 2001
Synthesis of Homochiral 5-and 8-Substituted 2-[((2-(2,6-Dimethoxyphenoxy)ethyl)amino)methyl]-1,4-... more Synthesis of Homochiral 5-and 8-Substituted 2-[((2-(2,6-Dimethoxyphenoxy)ethyl)amino)methyl]-1,4-benzodioxanes and Electrophoretic Determination of Their Enantiomeric Excess.-Some title compounds like (VIII) and (XIV) are prepared in order to test their biological activity.
Rapid Communications in Mass Spectrometry, 2000
The Journal of Organic Chemistry, 2001
24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic func... more 24 after methylating, in the case of the synthesis of (S)-1 and (S)-2, the residual phenolic function of (R)-9 and (R)-16; (g) amination with 2-(2,6-dimethoxyphenoxy)ethylamine. The R enantiomers of 1-3 were synthesized by the same strategy as illustrated in Scheme 1 but starting from the tosyl ester of (R)-glycerol acetonide [(S)-4]. 2-(Benzyloxy)-3-fluorophenol used in the first step of the syntesis of (S)-3 and (R)-3 was prepared from 2-fluorophenol as outlined in Scheme 3. Esterification with acetyl chloride, followed by Fries rearrangement and benzylation of the resulting hydroxyketone 26, afforded 2-(benzyloxy)-3-fluoroacetophenone (27), which was converted into the corresponding phenyl acetate 28 by the Baeyer-Villiger reaction and finally submitted to methanolysis. The enantiomeric purity of the optical isomers of WB4101 and of its three novel analogues was initially investigated by applying chromatographic methods. However, their previous conversion into diastereomeric amides by reaction with optically pure R-methoxy-R-(trifluoromethyl)phenylacetyl chloride was required to obtain analytical HPLC separation, while attempts at direct resolution of the enantiomers by HPLC on chiral station-Scheme 2 Scheme 3 Notes