7 research outputs found
Therapeutic Peptides Targeting PPI in Clinical Development: Overview, Mechanism of Action and Perspectives
Targeting protein-protein interactions (PPIs) has been recently recognized as an emerging
therapeutic approach for several diseases. Up today, more than half a million PPI
dysregulations have been found to be involved in pathological events. The dynamic
nature of these processes and the involvement of large protein surfaces discouraged
anyway the scientific community in considering them promising therapeutic targets. More
recently peptide drugs received renewed attention since drug discovery has offered a
broad range of structural diverse sequences, moving from traditionally endogenous
peptides to sequences possessing improved pharmaceutical profiles. About 70
peptides are currently on the marked but several others are in clinical development. In
this review we want to report the update on these novel APIs, focusing our attention on the
molecules in clinical development, representing the direct consequence of the drug
discovery process of the last 10 years. The comprehensive collection will be classified
in function of the structural characteristics (native, analogous, heterologous) and on the
basis of the therapeutic targets. The mechanism of interference on PPI will also be reported
to offer useful information for novel peptide desig
Fast MacMillan's Imidazolidinone-Catalyzed Enantioselective Synthesis of Polyfunctionalized 4-Isoxazoline Scaffolds
The enantioselective 1,3-dipolar cycloaddition of nitrones and arylpropionaldehydes to generate highly functionalized scaffolds for application in drug discovery was herein investigated. The use of a second-generation MacMillan catalyst as hydrochloride salt consistently accelerated the reaction speed, allowing a decrease in the reaction time up to >100 times, still affording 4-isoxazolines with good to excellent enantiomeric ratios at room temperature. As a proof of concept, further functionalization of the isoxazoline core through Pd-catalyzed cross-coupling was performed, generating differently functionalized chemical architectures in high yield
From virtual screening hits targeting a cryptic pocket in BACE-1 to a nontoxic brain permeable multitarget anti-Alzheimer lead with disease-modifying and cognition-enhancing effects
Starting from six potential hits identified in a virtual screening campaign directed to a cryptic pocket of BACE-1, at the edge of the catalytic cleft, we have synthesized and evaluated six hybrid compounds, designed to simultaneously reach BACE-1 secondary and catalytic sites and to exert additional activities of interest for Alzheimer's disease (AD). We have identified a lead compound with potent in vitro activity towards human BACE-1 and cholinesterases, moderate Ab42 and tau antiaggregating activity, and brain permeability, which is nontoxic in neuronal cells and zebrafish embryos at concentrations above those required for the in vitro activities. This compound completely restored short- and long-term memory in a mouse model of AD (SAMP8) relative to healthy control strain SAMR1, shifted APP processing towards the non-amyloidogenic pathway, reduced tau phosphorylation, and increased the levels of synaptic proteins PSD95 and synaptophysin, thereby emerging as a promising disease-modifying, cognitionenhancing anti-AD lead
Ampicillin sodium: Isolation, identification and synthesis of the last unknown impurity after 60 years of clinical use
Ampicillin, discovered in 1958, was the first broad spectrum semisynthetic penicillin introduced into the market. Despite its wide use not all the impurities have been identified to date. Herein, the last unknown impurity present in commercially available medicines was isolated and identified. This impurity that accounts up to 0.8 in area % by HPLC (EP 10.0) in the Reference Listed Drugs (RLD) was characterized and identified to be the 16-keto penicillin G. The structure was confirmed by comparison with a chemically synthesized sample. The determination of the Relative Response Factor (RRF) of the impurity respect to the parent drug allowed to recalculate the real amount that is consistently below the reporting threshold
Palladium Catalyst Recycling for Heck-Cassar-Sonogashira Cross-Coupling Reactions in Green Solvent/Base Blend
The identification of a green, versatile, user-friendly, and efficient methodology is necessary to facilitate the use of Heck-Cassar-Sonogashira (HCS) cross-coupling reaction in drug discovery and industrial production in the pharmaceutical segment. The Heck-Cassar and Sonogashira protocols, using N-hydroxyethylpyrrolidone (HEP)/water/N,N,N\u2032,N\u2032-tetramethyl guanidine (TMG) as green solvent/base mixture and sulfonated phosphine ligands, allowed to recycle the catalyst, always guaranteeing high yields and fast conversion under mild conditions, with aryl iodides, bromides, and triflates. No catalyst leakage or metal contamination of the final product were observed during the HCS recycling. To our knowledge, a turnover number (TON) up to 2375, a turnover frequency (TOF) of 158\u2005h 121, and a process mass intensity (PMI) around 7 that decreased around 3 after solvent, base, and palladium recovery, represent one of the best results to date using a sustainable protocol. The Heck-Cassar protocol using sSPhos was successfully applied to the telescoped synthesis of Erlotinib (TON: 1380; TOF: 46\u2005h 121)
Steps towards sustainable solid phase peptide synthesis: use and recovery of N-octyl pyrrolidone
The investigation of new green biogenic pyrrolidinones as alternative solvents to N,N-dimethylformamide
(DMF) for solid phase peptide synthesis (SPPS) led to the identification of N-octyl pyrrolidone (NOP) as
the best candidate. NOP showed good performances in terms of swelling, coupling efficiency and low
isomerization generating peptides with very high purity. A mixture of NOP with 20% dimethyl carbonate
(DMC) allowed a decrease in solvent viscosity, making the mixture suitable for the automated solid-phase
protocol. Aib-enkephalin and linear octreotide were successfully used to test the methodologies. It is
worth noting that NOP, DMC and the piperidine used in the deprotection step could be easily recovered
by direct distillation from the process waste mixture. The process mass intensity (PMI), being reduced by
63\u201366%, achieved an outstanding value representing a clear step forward in achieving green SPPS
Palladium Catalyst Recycling for HeckâCassarâSonogashira CrossâCoupling Reactions in Green Solvent/Base Blend
The identification of a green, versatile, user-friendly, and efficient methodology is necessary to facilitate the use of Heck-Cassar-Sonogashira (HCS) cross-coupling reaction in drug discovery and industrial production in the pharmaceutical segment. The Heck-Cassar and Sonogashira protocols, using N-hydroxyethylpyrrolidone (HEP)/water/N,N,NâČ,NâČ-tetramethyl guanidine (TMG) as green solvent/base mixture and sulfonated phosphine ligands, allowed to recycle the catalyst, always guaranteeing high yields and fast conversion under mild conditions, with aryl iodides, bromides, and triflates. No catalyst leakage or metal contamination of the final product were observed during the HCS recycling. To our knowledge, a turnover number (TON) up to 2375, a turnover frequency (TOF) of 158â
hâ1, and a process mass intensity (PMI) around 7 that decreased around 3 after solvent, base, and palladium recovery, represent one of the best results to date using a sustainable protocol. The Heck-Cassar protocol using sSPhos was successfully applied to the telescoped synthesis of Erlotinib (TON: 1380; TOF: 46â
hâ1)