## 3 Biotransformation of Viniferins
### Prediction of Some Parameters That Describe Drug-Likeness  
The drug-like profile can be predicted using an efficient quantitative estimate of a drug-likeness (\(QED\)) parameter as the concept of desirability in connection with the PD characteristics of a compound. The calculation of \(QED\) via ADMETlab ver. 3.0 [67] for an individual molecule was based on its \(MW\), descriptors defining stereochemical properties, \(n_{\text{OHNH}}\), \(n_{\text{ON}}\), charge, aromaticity, log \(P\), and solubility. The \(QED\) descriptor helped to emphasize the differences between drugs and nondrugs. This approach may be essential in relation to the eventual screening and evaluation of compounds for which no success is probable within next phases of pre-clinical or clinical research [135; 136]. The predicted \(QED\) index ranged from 0.000 to 1.000 [67]; the closer the \(QED\) value to 1.000, the greater the probability that an analyzed compound could be a drug. [PERSON] et al. [137] introduced the brand new concept of an _MCE-18_ (Medicinal Chemistry Evolution-18) descriptor in the investigation of drug-likeness for biologically active molecules. The parameter can effectively evaluate the compounds following their innovativeness from the viewpoint of Medicinal Chemistry and Pharmacology as well as according to their potential to be convenient structural platforms for drug design and development. The calculation of a given descriptor was based on the nature and quality of 3D scaffolds of compounds containing a relatively higher \(n_{\text{C}}\) in the \(sp^{3}\) hybridization [137]. However, the \(Fsp^{3}\) parameter [75] introduced in previous paragraphs gained less significance in this approach [137]. The value of _MCE-18_\(\geq\) 45.000 generated via ADMETlab ver. 3.0 for individual molecules was suitable [67]. Several Notes on Structure-Physicochemical Properties-Antimicrobial Activity Relationships of Viniferins and Viniferin-Based Compounds  
Relationships Between the Structure and Activity of Chosen Viniferins and Viniferin-Based Compounds Against Chosen Gram-Positive Bacterial Strains  
The research in the field of viniferins, their derivatives, and analogues in relation to antimicrobial screening in vitro is very impressive. In fact, scientists and scientific teams worldwide have investigated hundreds of variously substituted viniferin-derived compounds. In regard to such extensive research, this section is devoted especially to the so-called 'classical' (dimeric and dehydrodimeric) viniferins and viniferin-derived molecules with extraordinary efficiency estimated in vitro against chosen Gram-positive bacteria, i.e., selected strains of _Staphylococcus aureus_, _Streptococcus pneumoniae_, and _Listeria monocytogenes_, respectively. The available information connected with the activity in vitro of these molecules against some Gram-negative bacterial strains is also included to support the importance of systematic research aimed at particular naturally occurring viniferins, their semi-synthetic and synthetic derivatives, which could possibly be utilized for improvement in human health. In addition, the authors of the current review paper include information, if available in the scientific literature, on the predicted interactions between the considered compounds and their desired biological targets. [PERSON] et al. [138] synthesized and tested in vitro a set of structurally different still-benoids, including **trans-\(\delta\)-viniferin (17)**, **trans-\(\epsilon\)-viniferin (19)**, and their more lipophilic derivatives (Figure 8) containing a double bond between C2 and C3 of the benzo[\(b\)]furan system, i.e., **dehydro-\(\delta\)-viniferin (20)** and **dehydro-\(\epsilon\)-viniferin** (also known as **viniferin****furan**; **21)**, against a panel of Gram-positive and Gram-negative bacteria, including _S. aureus_ ATCC 25923 and _Pseudomonas aeruginosa_ ATCC 27853 (Gram-negative bacterium), respectively. The considered compounds showed notable efficacy mainly against _S.