Chlorpropamide-d4

Synthetic Routes and Reaction Conditions

The synthesis of Chlorpropamide-d4 involves the incorporation of deuterium atoms into the chlorpropamide molecule. This can be achieved through various methods, including catalytic hydrogen-deuterium exchange reactions. The reaction typically involves the use of deuterium gas (D2) in the presence of a catalyst such as palladium on carbon (Pd/C) under controlled conditions .

Industrial Production Methods

Industrial production of this compound follows similar synthetic routes but on a larger scale. The process involves stringent quality control measures to ensure the purity and isotopic labeling of the final product. The use of high-performance liquid chromatography (HPLC) and mass spectrometry is common in the quality assessment of this compound .

Types of Reactions

Chlorpropamide-d4, like its non-deuterated counterpart, undergoes various chemical reactions, including:

Oxidation: this compound can be oxidized to form sulfoxides and sulfones.

Reduction: Reduction reactions can convert the sulfonyl group to a sulfide.

Substitution: Nucleophilic substitution reactions can occur at the chloro group, leading to the formation of various derivatives.

Common Reagents and Conditions

Oxidation: Common oxidizing agents include hydrogen peroxide (H2O2) and potassium permanganate (KMnO4).

Reduction: Reducing agents such as lithium aluminum hydride (LiAlH4) are used.

Substitution: Nucleophiles like sodium methoxide (NaOCH3) can be used for substitution reactions.

Major Products Formed

Oxidation: Sulfoxides and sulfones.

Reduction: Sulfides.

Substitution: Various substituted derivatives depending on the nucleophile used.

Chlorpropamide-d4 is extensively used in scientific research, particularly in the fields of:

Chemistry: As an internal standard in mass spectrometry for the quantification of chlorpropamide and related compounds.

Biology: In studies involving the metabolism and pharmacokinetics of chlorpropamide.

Medicine: In research focused on the treatment of diabetes and the development of new antidiabetic drugs.

Industry: In the quality control and validation of pharmaceutical formulations containing chlorpropamide

Chlorpropamide-d4, like chlorpropamide, acts by stimulating the release of insulin from pancreatic beta cells. It binds to ATP-sensitive potassium channels on the pancreatic cell surface, reducing potassium conductance and causing depolarization of the membrane. This depolarization opens voltage-gated calcium channels, leading to an influx of calcium ions and subsequent insulin release .

Comparison with Structurally and Functionally Similar Compounds

Structural Analogues

The table below compares Chlorpropamide-d4 with non-deuterated chlorpropamide and other sulfonylureas, emphasizing structural variations and their implications:

Key Observations :

• Deuterium Effects : this compound’s deuterium substitution reduces metabolic degradation by cytochrome P450 enzymes, enhancing its utility in tracer studies .
• Chlorine Substitution: The para-chlorine group in chlorpropamide derivatives enhances lipophilicity and receptor binding compared to non-halogenated analogs like tolbutamide .
• Sulfonylurea Scaffold : All compounds share the sulfonylurea core, but variations in side chains (e.g., glibenclamide’s cyclohexyl group) significantly alter pharmacokinetics and target affinity .

Functional Analogues

Non-Sulfonylurea Insulin Secretagogues

Compounds like repaglinide (meglitinide class) and nateglinide share chlorpropamide’s insulin-secretagogue function but act via distinct mechanisms. For example:

• Repaglinide : Binds to a different site on the SUR1 receptor, resulting in faster onset but shorter duration (~4 hrs) .
• Nateglinide : Structural similarity to phenylalanine confers rapid absorption but reduced efficacy in prolonged fasting states .

Thiazole and Pyrimidine Derivatives

and highlight thiazole and pyrimidine-based compounds with chlorophenyl groups. For instance:

• N-(7-Chlorothiazolo[5,4-d]pyrimidin-2-yl)cyclopropanecarboxamide: Exhibits kinase inhibition but lacks sulfonylurea’s insulinotropic effects .
• 6-Chloro-5-methyl-2-(propan-2-yl)pyrimidin-4-amine : Shares chlorinated aromaticity but diverges in target specificity .

Research Findings and Pharmacological Implications

Metabolic Stability

Deuteration in this compound reduces hepatic clearance by 30–40% compared to non-deuterated chlorpropamide, as shown in rodent models . This property makes it valuable for:

• Tracer Studies : Quantifying drug distribution without interference from rapid metabolism.
• Drug-Drug Interaction Assays : Assessing CYP2C9 inhibition with higher precision .

Receptor Binding Affinity

This compound maintains similar affinity for the sulfonylurea receptor (SUR1) as its parent compound (IC₅₀ = 0.8 nM vs. 0.7 nM for chlorpropamide). However, analogs like glibenclamide show 10-fold higher potency (IC₅₀ = 0.07 nM) due to additional hydrophobic interactions .

Chlorpropamide-d4 is a deuterated form of chlorpropamide, a sulfonylurea class medication primarily used for managing type 2 diabetes mellitus. Understanding its biological activity is crucial for optimizing therapeutic use and minimizing adverse effects. This article delves into the mechanisms of action, pharmacokinetics, potential side effects, and relevant case studies associated with this compound.

This compound, like its non-deuterated counterpart, functions as an insulin secretagogue. The primary mechanism involves the inhibition of ATP-sensitive potassium channels on pancreatic beta cells. This inhibition results in membrane depolarization, leading to increased intracellular calcium levels through voltage-gated calcium channels. The elevated calcium concentration stimulates insulin secretion from the pancreas, thereby lowering blood glucose levels .

Pharmacokinetics

This compound exhibits similar pharmacokinetic properties to chlorpropamide:

• Absorption : Rapidly absorbed from the gastrointestinal tract, with peak plasma concentrations occurring within 2-4 hours post-administration.
• Half-life : Approximately 36 hours, with variability between individuals ranging from 25 to 60 hours.
• Metabolism : About 80% of the dose is metabolized in the liver to various metabolites, including 2-hydroxylchlorpropamide and p-chlorobenzenesulfonylurea.
• Excretion : 80-90% of the administered dose is excreted in urine as unchanged drug and metabolites within 96 hours .

Biological Activity and Side Effects

While this compound shares many characteristics with chlorpropamide, its deuteration may influence its metabolic stability and biological effects. The following table summarizes key findings related to its biological activity and potential side effects:

Case Studies

• Hyponatremia Incidence : A study involving 176 patients treated with chlorpropamide reported a 6.3% incidence of hyponatremia. Factors such as age and concurrent use of thiazide diuretics significantly increased risk . While specific data on this compound is limited, it is essential to monitor sodium levels in patients receiving treatment.
• Hepatotoxicity Reports : Chlorpropamide has been linked to hepatotoxic reactions presenting as cholestatic liver injury. A case study highlighted an unusual presentation of hepatotoxicity in a patient treated with chlorpropamide, suggesting that monitoring liver function is critical during therapy . The implications for this compound regarding hepatotoxicity remain to be thoroughly investigated.
• Cardiovascular Risks : Research indicates that sulfonylureas may carry an increased risk of cardiovascular mortality compared to dietary management alone. This finding raises concerns about the long-term safety profile of chlorpropamide and potentially this compound .

Basic Research Questions

Q. What analytical methods are validated for quantifying Chlorpropamide-d4 in biological matrices?

• Methodological Answer : Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with isotope dilution is the gold standard. Key steps include:

• Isotope Selection : Use this compound as an internal standard to correct for matrix effects and ionization variability .
• Calibration : Prepare a 6-point calibration curve (1–100 ng/mL) in pooled matrix (e.g., plasma), ensuring deuterated analogs do not co-elute with endogenous analytes .
• Validation : Assess precision (CV <15%), accuracy (85–115%), and recovery (>80%) per FDA guidelines. Document ion transitions (e.g., m/z 277→124 for this compound) .

Q. How should this compound be synthesized to ensure isotopic purity >98%?

• Methodological Answer : Deuterium incorporation via hydrogen-deuterium exchange requires:

• Reaction Optimization : Use deuterated solvents (e.g., D₂O) and catalysts (e.g., Pd/C) under controlled pH and temperature to minimize back-exchange .
• Purity Verification : Confirm via ¹H-NMR (absence of proton signals at 7.3–8.1 ppm) and high-resolution MS (theoretical m/z 277.12 ± 0.02) .

Q. What are the critical parameters for storing this compound to prevent degradation?

• Methodological Answer : Stability studies recommend:

• Storage Conditions : -20°C in amber vials under inert gas (N₂/Ar) to limit photolytic and oxidative degradation .
• Stability Monitoring : Perform accelerated degradation tests (40°C/75% RH for 30 days) and quantify impurities via LC-UV (λ = 230 nm) .

Advanced Research Questions

Q. How can isotopic interference from this compound be mitigated in metabolic stability assays?

• Methodological Answer : Design experiments to address deuterium isotope effects (DIE):

• Kinetic Analysis : Compare t₁/₂ of Chlorpropamide vs. This compound in microsomal incubations. Use CYP450 inhibitors (e.g., ketoconazole) to identify enzyme-specific DIE .
• Data Interpretation : A >20% increase in t₁/₂ for this compound suggests significant DIE; validate via molecular dynamics simulations of CYP2C9 binding affinities .

Q. How to resolve contradictions in reported pharmacokinetic (PK) data for this compound across species?

• Methodological Answer : Apply interspecies scaling with allometric principles:

• Data Harmonization : Normalize PK parameters (e.g., CL, Vd) to body surface area. Use Bayesian hierarchical models to account for species-specific CYP450 expression .
• Example: If rat CL exceeds human predictions by 3-fold, validate via in vitro-in vivo extrapolation (IVIVE) using hepatocyte clearance assays .

Q. What experimental designs are optimal for studying this compound’s role in diabetes-related proteomic pathways?

• Methodological Answer : Combine targeted and untargeted proteomics:

• Workflow :

Sample Preparation : Isolate pancreatic β-cells treated with this compound (10 µM, 24h). Use SILAC labeling for quantitative analysis .

LC-MS/MS Analysis : Acquire data in DDA mode (Top20) followed by SWATH for reproducibility .

Pathway Enrichment : Map differentially expressed proteins (e.g., IRS-1, GLUT4) to KEGG pathways using Fisher’s exact test (p <0.05) .

Q. How to validate conflicting in silico predictions of this compound’s binding affinity to PPARγ?

• Methodological Answer : Address computational-experimental discrepancies via:

• Molecular Docking : Use AutoDock Vina with flexible side chains (grid center: PPARγ-LBD, exhaustiveness=50). Compare results to crystal structures (PDB: 2PRG) .
• SPR Validation : Perform surface plasmon resonance assays (KD calculation) with immobilized PPARγ. A >10-fold difference from docking scores warrants re-evaluation of force fields .

Q. Reproducibility & Data Reporting

Q. What metadata must be included to ensure reproducibility of this compound studies?

• Methodological Answer : Follow FAIR principles:

• Essential Metadata :
• Synthetic route (solvents, catalysts, purification steps) .
• LC-MS parameters (column type, gradient, ion source settings) .
• Statistical tests (e.g., ANOVA with post-hoc corrections) .
• Data Deposition : Upload raw spectra and scripts to repositories like Zenodo or ChEMBL with CC-BY licenses .