## 1 Introduction  
Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting approximately 1% of the global population over the age of 60 [1, 2, 3]. It is caused by the degeneration of dopaminergic neurons located in the _substantianigra pars compacta_[4]. This neuronal loss leads to a decrease in dopamine release in the _striatum_, which results in the hallmark symptoms of PD, which are bradykinesia, rigidity, postural instability, tremors, and a significant decline in patients' quality of life [5]. The diagnosis of PD still relies on clinical criteria and remains challenging [6], particularly in its early stages when symptoms may resemble those of other disorders [7] such as multisystem atrophy, progressive supranuclear palsy, essential tremor, and vascular or drug Parkinsonism [5; 6; 8]. Therefore, the use of tools that allow for an accurate and early diagnosis of PD is crucial, given their confirmed impact on both prognosis and treatment outcomes [9]. One such approach involves evaluating the integrity of the nigrostriatal dopaminergic pathway using dopamine active transporters (DATs) [10]. The DATs are a group of transmembrane proteins associated with chloride channels, located at the presynaptic terminals of dopaminergic neurons [11]. They are responsible for the reuptake of dopamine after its release into the synaptic cleft [11; 12]. In patients with PD, because of the degeneration of these neurons, the density of DATs is significantly reduced [13]. Non-invasive molecular neuroimaging techniques, such as SPECT (Single-Photon Emission Computed Tomography) and PET (Positron Emission Tomography), enable in vivo visualization of various tissues and organs using radiopharmaceuticals [12; 14]. Several PET and SPECT radiotracers have been developed to target DATs [15]. Among them are radio-iodinated cocaine analogues, such as \({}^{123}\)I-Ioflupane (\({}^{123}\)I-\(\infty\)-fluoropropyl-2\(\beta\)-carbomethoxy-3\(\beta\)-(4-iodophenyl)nortropane) and \({}^{123}\)I-\(\beta\)-CIT (\({}^{123}\)I-2\(\beta\)-carbomethoxy-3\(\beta\)-(4-iodophenyl)tropane) [16]. These SPECT radiopharmaceuticals are widely used to assess the integrity of the nigrostriatal dopaminergic pathway and have demonstrated good diagnostic sensitivity and specificity for suspected PD cases [15]. However, both tracers require pre-treatment with a thyroid-blocking agent to protect the thyroid gland from radioactive iodine uptake [17]. Additionally, imaging with \({}^{123}\)I-\(\beta\)-CIT must be conducted 24 h post-injection, which can be inconvenient for outpatient settings [18]. There are also PET radiotracers with affinity for DAT, such as \({}^{11}\)C-N-(3-iodoprop-2(\(E\))-enyl)-2\(\beta\)-carbomethoxy-3\(\beta\)-(4\({}^{\prime}\)-methylphenyl)nortropane (\({}^{11}\)C-PE2I) [16]. In spite of its high specificity, the short half-life of \({}^{11}\)C (approximately 20 min) limits its clinical utility, as it requires on-site cyclotron production [19]. These limitations underscore the need for the development of new DAT-targeting radiopharmaceuticals that offer improved pharmacokinetic properties and logistical advantages, enabling better assessment of the nigrostriatal pathway in the early diagnosis of PD. The estimated cost and time required to bring a new drug to market are approximately USD 2.8 billion and 7 to 12 years [20]. Moreover, of the roughly 40,000 compounds tested in animals, only five typically proceed to human trials, and just one in five of those that reach clinical studies ultimately receives approval [21]. This reflects a significant expenditure of financial, human, and time resources. In response, virtual (computational) screening has emerged as a promising alternative to the traditional \"trial-and-error\" approach in identifying new chemical entities with biological activity. As a result, the pharmaceutical industry has shown growing interest in computational methodologies [22].