4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride
[CAS# 106261-49-8]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Piperazine
• Name: 4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride
• Molecular Formula: C₁₃H₁₈N₂O₂.2(HCl)
• Molecular Weight: 316.23
• CAS Registry Number: 106261-49-8
• EC Number: 600-728-4
• SMILES: CN1CCN(CC1)CC2=CC=C(C=C2)C(=O)O.Cl.Cl

Properties

• Melting point: 305-307 $degree$C

Safety Data

• Hazard Symbols: GHS07;GHS08 Danger
• Risk Statements: H302-H315-H319-H334-H335
• Safety Statements: P233-P260-P261-P264-P264+P265-P270-P271-P280-P284-P301+P317-P302+P352-P304+P340-P305+P351+P338-P319-P321-P330-P332+P317-P337+P317-P342+P316-P362+P364-P403-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Eye irritation	Eye Irrit.	2A	H319
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332

Discovery and Applications

4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride is an organic compound belonging to the class of substituted piperazine derivatives with an aromatic carboxylic acid moiety. Compounds of this type have been widely investigated in medicinal chemistry due to their pharmacological potential, particularly in the modulation of central nervous system targets, enzyme inhibition, and receptor binding. Piperazine derivatives have been known since the late nineteenth century, and the systematic study of N-substituted piperazines, including those carrying methyl groups or linked to aromatic systems, emerged in the mid-twentieth century as researchers explored synthetic scaffolds for drug development. Structurally, this compound consists of a benzoic acid core substituted at the para position with a methylene-linked 4-methylpiperazine group. The piperazine ring contains a tertiary nitrogen, while the carboxyl group of the benzoic acid provides acidic character, allowing the formation of the dihydrochloride salt. Salts of this type are typically used to improve solubility, stability, and handling characteristics, which are critical in both laboratory synthesis and pharmaceutical formulations. The synthetic preparation of this compound involves the reaction of 4-(chloromethyl)benzoic acid with 1-methylpiperazine, followed by salt formation with hydrochloric acid to yield the dihydrochloride. The methylene linkage between the aromatic ring and the piperazine nitrogen is a common structural feature that allows for flexibility and provides an optimal distance between functional groups, which can influence binding to biological targets. The methyl group on the piperazine ring further modulates electronic and steric properties, affecting both solubility and interaction with enzymes or receptors. 4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride has been explored primarily as an intermediate or active moiety in drug development programs. Piperazine-substituted benzoic acids are commonly studied for their potential as enzyme inhibitors, including kinases, as well as modulators of neurotransmitter receptors. The combination of a carboxylic acid group and a substituted piperazine provides both hydrogen bonding and ionic interaction capabilities, which are important in ligand-receptor binding studies. The structural motif also allows further chemical modification, enabling medicinal chemists to generate analogs with improved potency, selectivity, or pharmacokinetic properties. In addition to medicinal applications, compounds with this structural framework have been used as building blocks in synthetic organic chemistry. The carboxylic acid group can be converted into esters, amides, or activated intermediates for coupling reactions, while the piperazine nitrogen can undergo alkylation or acylation. This versatility makes the compound valuable in multistep synthetic sequences designed to produce more complex molecules for research or pharmaceutical purposes. The dihydrochloride form provides additional advantages in terms of stability and solubility. By forming a crystalline salt, the compound becomes easier to purify and handle, and the solubility in aqueous systems is improved, facilitating both laboratory use and potential pharmaceutical formulation. Compounds of this type have been subjected to spectroscopic and analytical characterization to confirm structure and purity, including nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry. Overall, 4-[(4-Methylpiperazin-1-yl)methyl]benzoic acid dihydrochloride illustrates the utility of piperazine-substituted aromatic acids in synthetic and medicinal chemistry. Its structural features, including the aromatic carboxylic acid, methylene linker, and substituted piperazine, make it a versatile intermediate and a pharmacologically relevant scaffold. Research on such compounds has contributed to the development of new synthetic strategies and enhanced understanding of molecular interactions relevant to drug design.

References

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