Evaluation of Anti-Alzheimer Activity of Synthetic Coumarins by Combination of in Vitro and in Silico Approaches.

Series of synthetic coumarin derivatives (1-16) were tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), two enzymes linked to the pathology of Alzheimer's disease (AD). Compound 16 was the most active AChE inhibitor with IC50 32.23±2.91 µM, while the reference (galantamine) had IC50 =1.85±0.12 µM. Compounds 9 (IC50 75.14±1.82 µM), 13 (IC50 =16.14±0.43 µM), were determined to be stronger BChE inhibitors than the reference galantamine (IC50 =93.53±2.23 µM). The IC50 value of compound 16 for BChE inhibition (IC50 =126.56±11.96 µM) was slightly higher than galantamine. The atomic interactions between the ligands and the key amino acids inside the binding cavities were simulated to determine their ligand-binding positions and free energies. The three inhibitory coumarins (9, 13, 16) were next tested for their effects on the genes associated with AD using human neuroblastoma (SH-SY5Y) cell lines. Our data indicate that they could be considered for further evaluation as new anti-Alzheimer drug candidates.

Exploiting the Propagation of Constrained Variables for Enhanced HDX-MS Data Optimization.

Nonlinear programming has found useful applications in protein biophysics to help understand the microscopic exchange kinetics of data obtained using hydrogen-deuterium exchange mass spectrometry (HDX-MS). Finding a microscopic kinetic solution for HDX-MS data provides a window into local protein stability and energetics allowing them to be quantified and understood. Optimization of HDX-MS data is a significant challenge, however, due to the requirement to solve a large number of variables simultaneously with exceptionally large variable bounds. Modeled rates are frequently uncertain with an explicate dependency on the initial guess values. In order to enhance the search for a minimum solution in HDX-MS optimization, the ability of selected constrained variables to propagate throughout the data is considered. We reveal that locally bound constrained optimization induces a global effect on all variables. The global response to local constraints is large and surprisingly long-range, but the outcome is unpredictable, unexpectedly decreasing the overall accuracy of certain data sets depending on the stringency of the constraints. Utilizing previously described in-house validation criteria based on covariance matrices, a method is described that is able to accurately determine whether constraints benefit or impair the optimization of HDX-MS data. From this, we establish a new two-stage method for our online optimizer HDXmodeller that can effectively leverage locally bound variables to enhance HDX-MS data modeling.

Characterization and Management of Noise in HDX-MS Data Modeling.

Quantification of hydrogen deuterium exchange (HDX) kinetics can provide information on the stability of individual amino acids in proteins by finding the degree to which the local backbone environment corresponds to that of a random coil. When characterized by mass spectrometry, extraction of HDX kinetics is not possible because different residue exchange rates become merged depending on the peptides that are formed during proteolytic digestion. We have recently developed an advanced programming tool called HDXmodeller, which enables the exchange rates of individual amino acids to be understood by optimization of low-resolution HDX-mass spectrometry (MS) data. HDXmodeller is also uniquely able to appraise each optimization and quantify the accuracy of modeled exchange rates ab initio using a novel autovalidation method based on a covariance matrix. Here, we address the noise-handling capabilities of HDXmodeller and demonstrate the effectiveness of the algorithm on self-inconsistent datasets. Reference intervals for experimental HDX-MS data are also derived, and this information is presented in an updated online workflow for HDXmodeller, allowing users to evaluate the consistency of their data. The development of a modified version of HDXmodeller is also discussed with enhanced noise-handling capability brought about through loss function optimization. Changes in optimizer accuracy with different loss functions are also demonstrated along with the effectiveness of HDXmodeller to select the most effective optimizer for different data using currently embedded autovalidation criteria.

Combined molecular modeling and cholinesterase inhibition studies on some natural and semisynthetic O-alkylcoumarin derivatives.

Coumarins of synthetic or natural origins are an important chemical class exerting diverse pharmacological activities. In the present study, 26 novel O-alkylcoumarin derivatives were synthesized and have been tested at 100 µM for their in vitro inhibitory potential against acetylcholinesterase (AChE) and butyrlcholinesterase (BChE) targets which are the key enzymes playing role in the pathogenesis of Alzheimer's disease. Among the tested coumarins, none of them could inhibit AChE, whereas 12 of them exerted a marked and selective inhibition against BChE as compared to the reference (galanthamine, IC50 = 46.58 ±â€¯0.91 µM). In fact, 10 of the active coumarins showed higher inhibition (IC50 = 7.01 ±â€¯0.28 µM - 43.31 ±â€¯3.63 µM) than that of galanthamine. The most active ones were revealed to be 7-styryloxycoumarin (IC50 = 7.01 ±â€¯0.28 µM) and 7-isopentenyloxy-4-methylcoumarin (IC50 = 8.18 ±â€¯0.74 µM). In addition to the in vitro tests, MetaCore/MetaDrug binary QSAR models and docking simulations were applied to evaluate the active compounds by ligand-based and target-driven approaches. The predicted pharmacokinetic profiles of the compounds suggested that the compounds reveal lipophilic character and permeate blood brain barrier (BBB) and the ADME models predict higher human serum protein binding percentages (>50%) for the compounds. The calculated docking scores indicated that the coumarins showing remarkable BChE inhibition possessed favorable free binding energies in interacting with the ligand-binding domain of the target. Therefore, our results disclose that O-alkylcoumarins are promising selective inhibitors of cholinesterase enzymes, particularly BChE in our case, which definitely deserve further studies.

Structural Investigation of the Dopamine-2 Receptor Agonist Bromocriptine Binding to Dimeric D2HighR and D2LowR States.

The active (D2HighR) and inactive (D2LowR) states of dimeric dopamine D2 receptor (D2R) models were investigated to clarify the binding mechanisms of the dopamine agonist bromocriptine, using Molecular Dynamics (MD) simulation. The aim of this comprehensive study was to investigate the critical effects of bromocriptine binding on each distinct receptor conformation. The different binding modes of the bromocriptine ligand in the active and inactive states have a significant effect on the conformational changes of the receptor. Based on the MM/GBSA approach, the calculated binding enthalpies of bromocriptine demonstrated selectivity toward the D2HighR active state. There is good agreement between the calculated and experimentally measured D2HighR selectivity. In the ligand-binding site, the key amino acids identified for D2HighR were Asp114(3.32) and Glu95(2.65), and for D2LowR, it was Ser193(5.42). Moreover, analysis of replicate MD trajectories demonstrated that the bromocriptine structure was more rigid at the D2HighR state and more flexible at the D2LowR state. However, the side chains of the ligand-receptor complex of D2HighR showed larger variations relative to the corresponding regions of D2LowR. The present study is part of an ongoing research program to study D2R conformational changes during ligand activation and to evaluate the conformational state selectivity for ligand binding.

Synthesis, anticholinesterase activity and molecular modeling study of novel carbamate-substituted thymol/carvacrol derivatives.

New thymol and carvacrol derivatives with the carbamate moiety were synthesized and their inhibitory effects on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) were evaluated. 5-isopropyl-2-methylphenyl(3-fluorophenyl)carbamate (29) was found to be the most potent AChE inhibitor with IC50 values of 2.22µM, and 5-isopropyl-2-methylphenyl (4-fluorophenyl)carbamate (30) exhibited the strongest inhibition against BuChE with IC50 value of 0.02µM. Additionally, the result of H4IIE hepatoma cell toxicity assay for compounds 18, 20, 29, 30 and 35 showed negligible cell death at 0.07-10µM. Moreover in order to better understand the inhibitory profiles of these molecules, molecular modeling studies were applied. Binding poses of studied compounds at the binding pockets of AChE and BuChE targets were determined. Predicted binding energies of these compounds as well as structural and dynamical profiles of molecules at the target sites were estimated using induced fit docking (IFD) algorithms and post-processing molecular dynamics (MD) simulations methods (i.e., Molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) approaches).

The synthesis of novel sulfamides derived from ß-benzylphenethylamines as acetylcholinesterase, butyrylcholinesterase and carbonic anhydrase enzymes inhibitors.

In this study, a series of novel ß-benzylphenethylamines and their sulfamide derivatives were synthesized starting from (Z)-2,3-diphenylacrylonitriles. Pd-C catalysed hydrogenation of diphenylacrylonitriles, reduction of propanenitriles with LiAlH4 in the presence of AlCl3 followed by addition of conc. HCl afforded ß-benzylphenethylamine hydrochloride salts. The reactions of these amine hydrochloride salts with chlorosulfonyl isocyanate (CSI) in the presence of tert-BuOH and excess Et3N gave sulfamoylcarbamates. Removing of Boc group from the synthesized sulfamoylcarbamates with trifluoroacetic acid (TFA) yielded novel sulfamides in good yields. These novel sulfamides derived from ß-benzylphenethylamines were effective inhibitors of the cytosolic carbonic anhydrase I and II isoenzymes (hCA I and II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with Ki values in the range of 0.278-2.260nM for hCA I, 0.187-1.478nM for hCA II, 0.127-2.452nM for AChE and 0.494-1.790nM for BChE. The inhibitory effects of the synthesized novel sulfamides derived from ß-benzylphenethylamines were compared to those of acetazolamide and dorzolamide as clinical hCA I and II isoenzymes inhibitors and tacrine as a clinical AChE and BChE enzymes inhibitors. In addition to in vitro tests, molecular modeling approaches are implemented not only for prediction of the binding affinities of the compounds but also to study their inhibition mechanisms in atomic level at the catalytic domains.

Effects of propolis, caffeic acid phenethyl ester, and pollen on renal injury in hypertensive rat: An experimental and theoretical approach.

The objective of this study was to evaluate the antioxidant effects of propolis, caffeic acid phenethyl ester (CAPE; active compound in propolis), and pollen on biochemical oxidative stress biomarkers in rat kidney tissue inhibited by Nω -nitro-L-arginine methyl ester (L-NAME). The biomarkers evaluated were paraoxonase (PON1), oxidative stress index (OSI), total antioxidant status (TAS), total oxidant status (TOS), asymmetric dimethylarginine (ADMA), and nuclear factor kappa B (NF-κB). TAS levels and PON1 activity were significantly decreased in kidney tissue samples in the L-NAME-treated group (P < 0.05). The levels of TAS and PONI were higher in the L-NAME plus propolis, CAPE, and pollen groups compared with the L-NAME-treated group. TOS, ADMA, and NF-κB levels were significantly increased in the kidney tissue samples of the L-NAME-treated group (P < 0.05). However, these parameters were significantly lower in the L-NAME plus propolis, CAPE, and pollen groups (P < 0.05) compared with rats administered L-NAME alone (P < 0.05). Furthermore, the binding energy of CAPE within catalytic domain of glutathione reductase (GR) enzyme as well as its inhibitory mechanism was determined using molecular modeling approaches. In conclusion, experimental and theoretical data suggested that oxidative alterations occurring in the kidney tissue of chronic hypertensive rats may be prevented via active compound of propolis, CAPE administration.

Characterization, in Vivo Evaluation, and Molecular Modeling of Different Propofol-Cyclodextrin Complexes To Assess Their Drug Delivery Potential at the Blood-Brain Barrier Level.

In this study, we investigated the ability of the general anesthetic propofol (PR) to form inclusion complexes with modified ß-cyclodextrins, including sulfobutylether-ß-cyclodextrin (SBEßCD) and hydroxypropyl-ß-cyclodextrin (HPßCD). The PR/SBEßCD and PR/HPßCD complexes were prepared and characterized, and the blood-brain barrier (BBB) permeation potential of the formulated PR was examined in vivo for the purpose of controlled drug delivery. The PR/SBEßCD complex was found to be more stable in solution with a minimal degradation constant of 0.25 h-1, a t1/2 of 2.82 h, and a Kc of 5.19 × 103 M-1 and revealed higher BBB permeability rates compared with the reference substance (PR-LIPURO) considering the calculated brain-to-blood concentration ratio (logBB) values. Additionally, the diminished PR binding affinity to SBEßCD was confirmed in molecular dynamics simulations by a maximal Gibbs free energy of binding (ΔGbind = -18.44 kcal·mol-1), indicating the more rapid PR/SBEßCD dissociation. Overall, the results demonstrated that SBEßCD has the potential to be used as a prospective candidate for drug delivery vector development to improve the pharmacokinetic and pharmacodynamic properties of general anesthetic agents at the BBB level.

Acetylcholinesterase and carbonic anhydrase inhibitory properties of novel urea and sulfamide derivatives incorporating dopaminergic 2-aminotetralin scaffolds.

In the present study a series of urea and sulfamide compounds incorporating the tetralin scaffolds were synthesized and evaluated for their acetylcholinesterase (AChE), human carbonic anhydrase (CA, EC 4.2.1.1) isoenzyme I, and II (hCA I and hCA II) inhibitory properties. The urea and their sulfamide analogs were synthesized from the reactions of 2-aminotetralins with N,N-dimethylcarbamoyl chloride and N,N-dimethylsulfamoyl chloride, followed by conversion to the corresponding phenols via O-demethylation with BBr3. The novel urea and sulfamide derivatives were tested for inhibition of hCA I, II and AChE enzymes. These derivatives exhibited excellent inhibitory effects, in the low nanomolar range, with Ki values of 2.61-3.69nM against hCA I, 1.64-2.80nM against hCA II, and in the range of 0.45-1.74nM against AChE. In silico techniques such as, atomistic molecular dynamics (MD) and molecular docking simulations, were used to understand the scenario of the inhibition mechanism upon approaching of the ligands into the active site of the target enzymes. In light of the experimental and computational results, crucial amino acids playing a role in the stabilization of the enzyme-inhibitor adducts were identified.

Discovering novel carbonic anhydrase type IX (CA IX) inhibitors from seven million compounds using virtual screening and in vitro analysis.

Carbonic anhydrase type IX (CA IX) enzyme is mostly over expressed in different cancer cell lines and tumor tissues. Potent CA IX inhibitors can be effective for adjusting the pH imbalance in tumor cells. In the present work, we represented the successful application of high throughput virtual screening (HTVS) of large dataset from ZINC database included of ∼7 million compounds to discover novel inhibitors of CA IX. HTVS and molecular docking were performed using consequence Glide/standard precision (SP), extra precision (XP) and induced fit docking (IFD) molecular docking protocols. For each compound, docking code calculates a set of low-energy poses and then exhaustively scans the binding pocket of the target with small compounds. Novel CA IX inhibitor candidates were suggested based on molecular modeling studies and a few of them were tested using in vitro analysis. These compounds were determined as good inhibitors against human CA IX target with Ki in the range of 0.85-1.58 µM. In order to predict the pharmaceutical properties of the selected compounds, ADME (absorption, distribution, metabolism and excretion) analysis was also carried out.

In silico investigation of PARP-1 catalytic domains in holo and apo states for the design of high-affinity PARP-1 inhibitors.

The rational design of high-affinity inhibitors of poly-ADP-ribose polymerase-1 (PARP-1) is at the heart of modern anti-cancer drug design. While relevance of enzyme to DNA repair processes in cellular environment is firmly established, the structural and functional understanding of the main determinants for high-affinity ligands controlling PARP-1 activity is still lacking. The conserved active site of PARP-1 represents an ideal target for inhibitors and may offer a novel target at the treatment of breast cancer. To fill the gap in the structural knowledge, we report on the combination of molecular dynamics (MD) simulations, principal component analysis (PCA), and conformational analysis that analyzes in great details novel binding mode for a number of inhibitors at the PARP-1. While optimization of the binding affinity for original target is an important goal in the drug design, many of the promising molecules for treatment of the breast cancer are plagued by significant cardiotoxicity. One of the most common side-effects reported for a number of polymerase inhibitors is its off-target interactions with cardiac ion channels and hERG1 channel, in particular. Thus, selected candidate PARP-1 inhibitors were also screened in silico at the central cavities of hERG1 potassium ion channel.

Molecular Simulations of Solved Co-crystallized X-Ray Structures Identify Action Mechanisms of PDEδ Inhibitors.

PDEδ is a small protein that binds and controls the trafficking of RAS subfamily proteins. Its inhibition protects initiation of RAS signaling, and it is one of the common targets considered for oncological drug development. In this study, we used solved x-ray structures of inhibitor-bound PDEδ targets to investigate mechanisms of action of six independent all-atom MD simulations. An analysis of atomic simulations combined with the molecular mechanic-Poisson-Boltzmann solvent accessible surface area/generalized Born solvent accessible surface area calculations led to the identification of action mechanisms for a panel of novel PDEδ inhibitors. To the best of our knowledge, this study is one of the first in silico investigations on co-crystallized PDEδ protein. A detailed atomic-scale understanding of the molecular mechanism of PDEδ inhibition may assist in the design of novel PDEδ inhibitors. One of the most common side effects for diverse small molecules/kinase inhibitors is their off-target interactions with cardiac ion channels and human-ether-a-go-go channel specifically. Thus, all of the studied PDEδ inhibitors are also screened in silico at the central cavities of hERG1 potassium channels.

Carbonic anhydrase inhibitors: Design, synthesis, kinetic, docking and molecular dynamics analysis of novel glycine and phenylalanine sulfonamide derivatives.

The inhibition of two human cytosolic carbonic anhydrase isozymes I and II, with some novel glycine and phenylalanine sulfonamide derivatives were investigated. Newly synthesized compounds G1-4 and P1-4 showed effective inhibition profiles with KI values in the range of 14.66-315µM for hCA I and of 18.31-143.8µM against hCA II, respectively. In order to investigate the binding mechanisms of these inhibitors, in silico docking studies were applied. Atomistic molecular dynamic simulations were performed for docking poses which utilize to illustrate the inhibition mechanism of used inhibitors into active site of CAII. These sulfonamide containing compounds generally were competitive inhibitors with 4-nitrophenylacetate as substrate. Some investigated compounds here showed effective hCA II inhibitory effects, in the same range as the clinically used sulfonamide, sulfanilamide or mafenide and might be used as leads for generating enzyme inhibitors possibly targeting other CA isoforms which have not been yet assayed for their interactions with such agents.

Fullerene-based inhibitors of HIV-1 protease.

A series of Fmoc-Phe(4-aza-C60)-OH of fullerene amino acid derived peptides have been prepared by solid phase peptide synthesis, in which the terminal amino acid, Phe(4-aza-C60)-OH, is derived from the dipolar addition to C60 of the Fmoc-Nα-protected azido amino acids derived from phenylalanine: Fmoc-Phe(4-aza-C60)-Lys3-OH (1), Fmoc-Phe(4-aza-C60)-Pro-Hyp-Lys-OH (2), and Fmoc-Phe(4-aza-C60)-Hyp-Hyp-Lys-OH (3). The inhibition constant of our fullerene aspartic protease PRIs utilized FRET-based assay to evaluate the enzyme kinetics of HIV-1 PR at various concentrations of inhibitors. Simulation of the docking of the peptide Fmoc-Phe-Pro-Hyp-Lys-OH overestimated the inhibition, while the amino acid PRIs were well estimated. The experimental results show that C60-based amino acids are a good base structure in the design of protease inhibitors and that their inhibition can be improved upon by the addition of designer peptide sequences.

Modeling and protein engineering studies of active and inactive states of human dopamine D2 receptor (D2R) and investigation of drug/receptor interactions.

Homology model structures of the dopamine D2 receptor (D2R) were generated starting from the active and inactive states of ß2-adrenergic crystal structure templates. To the best of our knowledge, the active conformation of D2R was modeled for the first time in this study. The homology models are built and refined using MODELLER and ROSETTA programs. Top-ranked models have been validated with ligand docking simulations and in silico Alanine-scanning mutagenesis studies. The derived extra-cellular loop region of the protein models is directed toward the binding site cavity which is often involved in ligand binding. The binding sites of protein models were refined using induced fit docking to enable the side-chain refinement during ligand docking simulations. The derived models were then tested using molecular modeling techniques on several marketed drugs for schizophrenia. Alanine-scanning mutagenesis and molecular docking studies gave similar results for marketed drugs tested. We believe that these new D2 receptor models will be very useful for a better understanding of the mechanisms of action of drugs to be targeted to the binding sites of D2Rs and they will contribute significantly to drug design studies involving G-protein-coupled receptors in the future.

Elucidation of conformational states, dynamics, and mechanism of binding in human κ-opioid receptor complexes.

Opioid G protein-coupled receptors (GPCRs) have been implicated in modulating pain, addiction, psychotomimesis, mood and memory, among other functions. We have employed the recently reported crystal structure of the human κ-opioid receptor (κ-OR) and performed molecular dynamics (MD), free energy, and ab initio calculations to elucidate the binding mechanism in complexes with antagonist JDTic and agonist SalA. The two systems were modeled in water and in DPPC lipid bilayers, in order to investigate the effect of the membrane upon conformational dynamics. MD and Atoms in Molecules (AIM) ab initio calculations for the complexes in water showed that each ligand was stabilized inside the binding site of the receptor through hydrogen bond interactions that involved residues Asp138 (with JDTic) and Gln115, His291, Leu212 (with SalA). The static description offered by the crystal structure was overcome to reveal a structural rearrangement of the binding pocket, which facilitated additional interactions between JDTic and Glu209/Tyr139. The role of Glu209 was emphasized, since it belongs to an extracellular loop that covers the binding site of the receptor and is crucial for ligand entrapment. The above interactions were retained in membrane complexes (SalA forms additional hydrogen bonds with Tyr139/312), except the Tyr139 interaction, which is abolished in the JDTic complex. For the first time, we report that JDTic alternates between a "V-shape" (stabilized via a water-mediated intramolecular interaction) and a more extended conformation, a feature that offers enough suppleness for effective binding. Moreover, MM-PBSA calculations showed that the more efficient JDTic binding to κ-OR compared to SalA (ΔGJDTic = -31.6 kcal mol(-1), ΔGSalA = -9.8 kcal mol(-1)) is attributed mostly to differences in electrostatic contributions. Importantly, our results are in qualitative agreement with the experiments (ΔGJDTic,exp = -14.4 kcal mol(-1), ΔGSalA,exp = -10.8 kcal mol(-1)). This study provides previously unattainable information on the dynamics of human κ-OR and insight on the rational design of drugs with improved pharmacological properties.

Carbonic anhydrase inhibitory properties of novel benzylsulfamides using molecular modeling and experimental studies.

In this study, a series of sulfamoyl carbamates and sulfamide derivatives were synthesized. Six commercially available benzyl amines and BnOH were reacted with chlorosulfonyl isocyanate (CSI) to give sulfamoyl carbamates. Pd-C catalyzed hydrogenolysis reactions of carbamates afforded sulfamides. The inhibition effects of novel benzylsulfamides on the carbonic anhydrase I, and II isoenzymes (CA I, and CA II) purified from fresh human blood red cells were determined by Sepharose-4B-L-Tyrosine-sulfanilamide affinity chromatography. In vitro studies were shown that all of novel synthesized benzylsulfamide analogs inhibited, concentration dependently, both hCA isoenzyme activities. The novel benzylsulfamide compounds investigated here exhibited nanomolar inhibition constants against the two isoenzymes. Ki values were in the range of 28.48±0.01-837.09±0.19nM and 112.01±0.01-268.01±0.22nM for hCAI and hCA II isoenzymes, respectively. Molecular modeling approaches were also applied for studied compounds.

X-ray crystalographic data, absolute configuration, and anticholinesterase effect of dihydromyricitrin 3-O-rhamnoside.

Based on our continuous effort to investigate chemistry and biology of the plant secondary metabolites, we were able to isolate a glycosidal flavonoid 1 from the Wild Egyptian Artichoke. The activity of dihydromyricetin 3-O-rhamnoside (sin. dihydromyricitrin, ampelopsin 3-O-rhamnoside) (1) against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE); its absolute configuration using X-ray crystallography were determined for the first time. Inhibitory activity of 1 against AChE and BChE enzymes were determined using a slightly modified version of Ellman's method. Compound 1 was revealed to have a potent inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 0.070 ± 0.008 and 0.071 ± 0.004 mM, respectively, where IC50 values of the reference drug (galanthamine) were 0.023 ± 0.15 and 0.047 ± 0.91 mM. Compound 1 could be a promising molecule against Alzheimer's disease.

7-Acetoxyhorminone from Salvia multicaulis Vahl. as Promising Inhibitor of 3-Hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) Reductase.

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is a key enzyme involved in cholesterol biosynthesis and one of the most important targets for the treatment of hypercholesterolemia. A limited number of studies on the HMG-CoA reductase inhibitory potential of natural products are available. Thus, in the current study, we aimed to test the HMG-CoA reductase inhibitory capacity of extracts from the roots and aerial parts of Salvia multicaulis Vahl., through activity-guided isolation. Our findings revealed that the root extract prepared with dichloromethane-acetone (1:1) showed the highest inhibition (71.97 ± 0.37%) at 100 µg/mL. The extract was then initially fractionated by column chromatography and the obtained fractions were monitored by thin layer chromatography. Fractions which were similar to each other were combined and a total of 15 fractions were obtained. Further conventional chromatographic studies were carried out on the active fractions. Based on these fractions, 10 known compounds, comprising 9 terpenes and 1 steroid derivative in total, were isolated and their structures were verified by a combination of IT-TOF-MS, and 1D and 2D NMR techniques. According to the enzyme inhibition data of the identified compounds, 7-acetoxyhorminone exerted the highest inhibition (84.15 ± 0.10%, IC50 = 63.6 ± 1.21 µg/mL). The molecular docking experiments on 7-acetoxyhorminone and horminone indicated that both compounds strongly bind to the active site of the enzyme.