The Antitumoral Effect In Ovo of a New Inclusion Complex from Dimethoxycurcumin with Magnesium and Beta-Cyclodextrin.

Breast cancer is one of the leading causes of death in the female population because of the resistance of cancer cells to many anticancer drugs used. Curcumin has cytotoxic activities against breast cancer cells, although it has limited use due to its poor bioavailability and rapid metabolic elimination. The synthesis of metal complexes of curcumin and curcuminoids is a relevant topic in the search for more active and selective derivatives of these molecular scaffolds. However, solubility and bioavailability are concomitant disadvantages of these types of molecules. To overcome such drawbacks, the preparation of inclusion complexes offers a chemical and pharmacologically safe option for improving the aqueous solubility of organic molecules. Herein, we describe the preparation of the inclusion complex of dimethoxycurcumin magnesium complex (DiMeOC-Mg, (4)) with beta-cyclodextrin (DiMeOC-Mg-BCD, (5)) in the stoichiometric relationship 1:1. This new inclusion complex's solubility in aqueous media phosphate buffer saline (PBS) was improved by a factor of 6x over the free metal complex (4). Furthermore, 5 affects cell metabolic rate, cell morphology, cell migration, induced apoptosis, and downregulation of the matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and signal transducer and activator of transcription-3 (STAT3) expression levels on MD Anderson metastasis breast-231 cancer (MDA-MB-231) cell lines. Results of an antitumor assay in an in ovo model showed up to 30% inhibition of tumor growth for breast cancer (MDA-MB-231) when using (5) (0.650 mg/kg dose) and 17.29% inhibition with the free homoleptic metal complex (1.5 mg/kg dose, (4)). While the formulation of inclusion complexes from metal complexes of curcuminoids demonstrates its usefulness in improving the solubility and bioavailability of these metallodrugs, the new compound (5) exhibits excellent potential for use as a therapeutic agent in the battle against breast cancer.

Larvicidal Activity against Spodoptera frugiperda of some Constituents from two Diospyros Species. In silico Pesticide-likeness Properties, Acetylcholinesterase Activity and Molecular Docking.

This report informs for the first time the chemical constituents of Diospyros xolocotzii and Diospyros digyna, the pesticidal and the acetylcholinesterase (AChE) inhibition potential of some compounds calculated by in silico approaches, the larvicidal activity against Spodoptera frugiperda of available compounds, the AChE inhibition of selected compounds, and the results of the molecular docking of the most active ones with this receptor. From the aerial parts of D. xolocotzii were isolated pentacyclic triterpenes (1-4, 6, 10, 11-13), phytosterols (15-17), and isodiospyrin (18), whereas the analysis of aerial parts of D. digyna conducted to the isolation of pentacyclic triterpenes (4, 5, 7-9, 11-14), (4S)-shinanolone (19), and scopoletin (20). For comparison purposes, origanal (21) was chemically prepared from 11. The in silico analysis showed that the tested compounds have pesticide potential. The larvicidal activities of 11>13>12 indicated that the increase of the oxidation degree at C-28 increases their bioactivity. Compounds 11 and 21 presented the higher inhibition in the acetylcholinesterase assay, and the higher binding energies, and for the interactionswith AChE by molecular docking. Both Diospyros species are sources of triterpenes with pesticidal potential and the molecular changes in lupane triterpenes correlate with the observed bioactivity and molecular docking.

Discovery of dual-action phenolic 4-arylidene-isoquinolinones with antioxidant and α-glucosidase inhibition activities.

A multicomponent-derived synthesis of arylidene isoquinolinones decorated with phenolic moieties is described. The series demonstrated good DPPH trapping and, in the case of sinapic acid-containing analogs, excellent activity against lipoperoxidation; EPR also demonstrated that one derivative scavenged hydroxyl radicals. In addition, some compounds showed excellent inhibition of α-glucosidase activity and, according to both Lineweaver-Burk plots and molecular docking, they act as non-competitive or mixed inhibitors. In vitro assay also demonstrated that two compounds significantly reduced the plasma glucose levels after sucrose administration. In summary, the studied isoquinolinones become novel compounds with dual action (antioxidant and α-glucosidase inhibition) against diabetes and related metabolic diseases, whose optimization would lead to more potent candidates.

Evaluation of selected natural sesquiterpenes as sensitizing agents of ß-lactam-resistant bacterial strains.

AIMS: To evaluate the capacity of fourteen sesquiterpenes to enhance the action of known antibiotics against two ß-lactam resistant strains, and to determine a possible mechanism of antibiotic sensitization by assessing their ability to inhibit a ß-lactamase enzyme. METHODS AND RESULTS: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of ß-lactams cefuroxime (CEFM) and cefepime (CPM) against Staphylococcus aureus 23MR and Escherichia coli 82MR strains in the absence and presence of subinhibitory concentrations of fourteen natural sesquiterpenes. (1R,4R)-4H-1,2,3,4-tetrahydro-1-hydroxycadalen-15-oic acid (5), xerantolide (8), estafiatin (11), and ambrosin (12) exhibited the best sensitizing effects in both strains. These compounds were able to reduce the MIC of CEFM by 2-fold (from 15.0 to 7.5 µg/mL) and CPM by 15-fold (from 0.9 to 0.06 µg/mL) in S. aureus 23MR. For E. coli 82MR, the MIC of CEFM was reduced up to 8-fold (from 120.0 to 15.0 µg/mL). In this strain, the activity of 8 and 11 surpassed that of clavulanic acid (positive reference), which reduced the MIC of CEFM from 120.0 to 60.0 µg/mL. To elucidate a possible mechanism of antibiotic sensitization, molecular docking studies were conducted with ß-lactamases. These studies revealed an affinity with the enzymes (energies > -4.93 kcal/mol) by the formation of hydrogen bonds with certain conserved amino acid residues within the active sites. However, the in vitro results indicated only marginal inhibition, with percentages <50%. CONCLUSIONS: The bioevaluations indicate that nine of fourteen sesquiterpenes enhance the action of CEFM and CPM against the ß-lactam resistant strains, and these compounds displayed moderate activity as inhibitors of ß-lactamase.

The Homoleptic Curcumin-Copper Single Crystal (ML2): A Long Awaited Breakthrough in the Field of Curcumin Metal Complexes.

The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L = curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry, also confirmed by EPR. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing Crystallinity was additionally assessed by XRD patterns. The log P value of the complex (2.3 ± 0.15) was determined showing the improvement in water solubility. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines, with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.

Withanolides from Datura ceratocaula and Datura discolor and their acetylcholinesterase inhibitory activity.

The investigation of the chemical constituents of Datura ceratocaula and D. discolor allowed to isolate three new withanolides, datucerolide A (1) from the first species, and datudiscolides A (8) and B (9) from the second. In addition, seven known withanolides and five ubiquitous compounds were isolated from these plants, along with 27-O-ß-d-glucopyranosyl dinnoxolide A (5), which was obtained as the tetraacetyl derivative 4. All the structures were elucidated by analyses of their spectroscopic and spectrometric data and that of dinnoxolide A (6) was confirmed by X-ray diffraction analysis. The structure 4 was assigned earlier to daturametelin G-Ac and that of 5 to datinolide B, therefore, it will be discussed whether these assignments are correct. On the other hand, the structure of datudiscolide A (8) was previously assigned to the aglycone of dinoxin B (14), however, a revision of its reported NMR data showed inconsistencies with the proposed structure. The inhibitory activity of withanolides 2, 3, 6-8, 12, and 13 against acetylcholinesterase enzyme (AChE) was evaluated. Compounds 6, 7, 12, and 13 exhibited the best activity with IC50 values ranging from 2.8 to 21.5 µM.

Phenolic Compounds from Wild Plant and In Vitro Cultures of Ageratina pichichensis and Evaluation of Their Antioxidant Activity.

Ageratina pichichensis, is commonly used in traditional Mexican medicine. In vitro cultures were established from wild plant (WP) seeds, obtaining in vitro plant (IP), callus culture (CC), and cell suspension culture (CSC) with the objective to determine total phenol content (TPC) and flavonoids (TFC), as well as their antioxidant activity by DPPH, ABTS and TBARS assays, added to the compound's identification and quantification by HPLC, from methanol extracts obtained by sonication. CC showed significantly higher TPC and TFC than WP and IP, while CSC produced 2.0-2.7 times more TFC than WP, and IP produced only 14.16% TPC and 38.8% TFC compared with WP. There were identified compounds such as epicatechin (EPI), caffeic acid (CfA), and p-coumaric acid (pCA) in in vitro cultures that were not found in WP. The quantitative analysis shows gallic acid (GA) as the least abundant compound in samples, whereas CSC produced significantly more EPI and CfA than CC. Despite these results, in vitro cultures show lower antioxidant activity than WP, for DPPH and TBARS WP > CSC > CC > IP and ABTS WP > CSC = CC > IP. Overall, A. pichichensis WP and in vitro cultures produce phenolic compounds with antioxidant activity, especially CC and CSC, which are shown to be a biotechnological alternative for obtaining bioactive compounds.

Lactols from Physalis grisea.

From the extracts of stems and leaves as well as of calyxes of Physalis grisea were isolated four withalactols, the new griselactols A (3) and B (6) and the known physapubescin (1) and peruvianolide E (2). Other four known compounds were also isolated, kaempferol 3-O-ß-sophoroside (5) and three sterols. The structures of compounds were elucidated by extensive spectroscopic data analyses, chemical and physical-chemical methods, including electronic circular dichroism (ECD), and by comparison with data described in the literature. The antihyperglycemic activity of the extracts and of the three more abundant metabolites (1, 3, and 5) was evaluated in the α-glucosidase inhibition assay.

Synthesis, biological evaluation, molecular docking studies and In-silico ADMET evaluation of pyrazines of pentacyclic triterpenes.

The semisynthesis of novel derivatives of lupeyl palmitate and 3ß-palmitoyloxy-olean-12-ene by introduction of a pyrazine at C-2 / C-3 and modifications of the relatively unexplored C-30 position of lupeol derivatives was conducted, and their cytotoxic and anti-inflammatory activities were evaluated. The derivatives 7, 10 and 11 significantly inhibited the tumor cell lines U251, K562, HCT-15, MCF-7 and SKLU-1, and compounds 7 and 11 were more active (IC50 25.4 ± 2.0 µM and 7.1 ± 0.4 µM, respectively) than the positive control (etoposide (IC50 31.5 ± 2.2 µM) in the tumor line PC-3. Introduction of the pyrazine at C-2 / C-3 in compounds 1 and 2 or modification at C-30 of compound 1 decreased the anti-inflammatory activity in the TPA-induced mouse ear edema. Following the results of the PASS online evaluation of the potential biological activity of the natural compounds and their derivatives, the inhibition of pNF-κB translocation to the prostate cancer (PC-3) cell nucleus was investigated and the binding mode of compounds 7, 10 and 11 with the human NF-κB receptor was explored by a molecular docking study. These derivatives bound directly or close to the amino acids that form the DNA recognition site. The ADMET physicochemical parameters of the fifteen compounds were further analyzed in silico using Molinspiration calculations indicating the potential of compounds 7, 10 and 11 for further investigation.

3ß-Palmitoyloxy-olean-12-ene analogs from Sapium lateriflorum (Euphorbiaceae): Their cytotoxic and anti-inflammatory properties and docking studies.

Ten compounds, including a new anti-inflammatory acyl triterpene, 3ß-palmitoyloxy-1ß,11α-dihydroxy-olean-12-ene, were isolated from the bioactive organic extract prepared from the leaves of Sapium lateriflorum (syn: S. nitidum). The isolated compounds were screened for their cytotoxic activity against selected human cancer cell lines and did not display significant activity. They were also evaluated as anti-inflammatory agents in mouse models (TPA-induced edema in the ear and in a carrageenan-induced paw edema model). The results indicated that the new compound, 3ß-palmitoyloxy-1ß,11α-dihydroxy-olean-12-ene, was the compound with major anti-inflammatory activity similar to that of indomethacin, being the hydroxyl at C-11 important for the observed activity. The results of docking studies of the 3ß-palmitoyloxy esters of olean-12-ene with NF-κB and with COX-2 receptors were consistent with possible molecular mechanisms of the anti-inflammatory activity.

Multicomponent synthesis and preliminary anti-inflammatory activity of lipophilic diphenylamines.

Non-Steroidal Anti-inflammatory Drugs (NSAIDs) are some of the most prescribed medications for pain but the incidence of adverse effects -especially during chronic treatment- points out the requirement of new analgesics. In this study, we showed an efficient two-steps synthesis of diphenylamine-containing dipeptides consisting of a multicomponent process followed by a Buchwald-Hartwig cross-coupling reaction. We prepared 16 diphenylamine derivatives and evaluated their in vivo anti-inflammatory activity through an ear edema model using 12-O-tetradecanoylpholbol-13-acetate. Furthermore, the toxicity of the more potent compounds in the Artemia salina model and their cell viability using murine RAW 264.7 cells is reported. The fluorinated compound 10k becomes a reliable candidate since it reduced the TPA-induced edema to 92%, lacked cytotoxicity against murine macrophages, and had minimal toxicity in Artemia salina.

Elemenolides from Zinnia peruviana and evaluation of their antibacterial and α-glucosidase inhibitory activities.

A phytochemical study from Zinnia peruviana L. resulted in the isolation of a new elemene-type sesquiterpene lactone, zinaflorin VI (1), along with the known elemenolides 2-5 and the flavone onopordin (6). The structures of these compounds were determined by analysis of their spectroscopic data. The antibacterial activity of the γ-elemenolides 1, 4, and 5 was evaluated. The δ-elemenolide juniperin (7), previously isolated from Zinnia juniperifolia, was included in this assay. Compounds 1 and 7 were active against Bacillus subtilis and Staphylococcus aureus with MICs = 32 and 64 µg/mL for compound 1 and MICs = 4 and 8 µg/mL for compound 7. The α-glucosidase inhibitory activity of compounds 1, and 4-7 was evaluated, but none of these compounds was found to be active.

Goat's Milk Intake Prevents Obesity, Hepatic Steatosis and Insulin Resistance in Mice Fed A High-Fat Diet by Reducing Inflammatory Markers and Increasing Energy Expenditure and Mitochondrial Content in Skeletal Muscle.

Goat's milk is a rich source of bioactive compounds (peptides, conjugated linoleic acid, short chain fatty acids, monounsaturated and polyunsaturated fatty acids, polyphenols such as phytoestrogens and minerals among others) that exert important health benefits. However, goat's milk composition depends on the type of food provided to the animal and thus, the abundance of bioactive compounds in milk depends on the dietary sources of the goat feed. The metabolic impact of goat milk rich in bioactive compounds during metabolic challenges such as a high-fat (HF) diet has not been explored. Thus, we evaluated the effect of milk from goats fed a conventional diet, a conventional diet supplemented with 30% Acacia farnesiana (AF) pods or grazing on metabolic alterations in mice fed a HF diet. Interestingly, the incorporation of goat's milk in the diet decreased body weight and body fat mass, improved glucose tolerance, prevented adipose tissue hypertrophy and hepatic steatosis in mice fed a HF diet. These effects were associated with an increase in energy expenditure, augmented oxidative fibers in skeletal muscle, and reduced inflammatory markers. Consequently, goat's milk can be considered a non-pharmacologic strategy to improve the metabolic alterations induced by a HF diet. Using the body surface area normalization method gave a conversion equivalent daily human intake dose of 1.4 to 2.8 glasses (250 mL per glass/day) of fresh goat milk for an adult of 60 kg, which can be used as reference for future clinical studies.

Hopane-type triterpenes from Cnidoscolus spinosus and their bioactivities.

Chemical investigation of the aerial parts of Cnidoscolus spinosus resulted in the isolation of relatively infrequent hopane-type triterpenes, 3ß-acetoxy-hop-22(29)-ene (1), first reported here as natural product, together with 3-oxo-hop-22(29)-ene (2), and 3ß-hydroxy-hop-22(29)-ene (3). ß-Amyrin palmitate and three phytosterols were also characterized. The structures of the compounds were established using spectroscopic methods, and those of 1 and 2 were confirmed by crystallographic analysis. Selected biological activities for the isolated hopane-type triterpenes were tested through a series of assays for determining the cytotoxic, anti-inflammatory, α-glucosidase inhibition and antiparasitic activities. Compounds 1-3 did not show cytotoxic activity, compound 1 displayed an important inhibitory effect in the mouse ear induced inflammation assay, and significantly inhibited the yeast α-glucosidase activity in vitro and in silico. Additionally, compounds 2 and 3 showed marginal activities against Trypanosoma cruzi and Leishmania mexicana. Therefore, the bioactivities of hopane-type triterpenes deserve further investigation, particularly their anti-inflammatory properties.

Structural Elucidation of Malonylcommunol and 6ß-Hydroxy-trans-communic Acid, Two Undescribed Diterpenes from Salvia cinnabarina. First Examples of Labdane Diterpenoids from a Mexican Salvia Species.

The aerial parts of Salvia cinnabarina afforded two undescribed labdane diterpenoids 1 and 2 (malonylcommunol and 6ß-hydroxy-trans-communic acid) along with two known labdane diterpenoids, trans-communic acid (3) and trans-communol (4). Additionally, seven known metabolites were also isolated; two isopimarane diterpenoids 5 and 6, two sesquiterpenoids identified as ß-eudesmol (7) and cryptomeridiol (8), and three aromatic compounds identified as phthalic acid (9), a mixture of tyrosol fatty acid esters (10) and the flavone salvigenine (11). While compounds compounds 1-3 showed significant inhibition of yeast α-glucosidase, compounds 2, 3 and 7 had no anti-inflammatory activity in the edema model induced by TPA. This paper is not only the first report on a wild population of Salvia cinnabarina, but also of the presence of labdane-type diterpenoids in a Mexican Salvia sp.

Recognition of antioxidants and photosensitizers in Dyssodia pinnata by EPR spectroscopy.

INTRODUCTION: Previous studies report the isolation mainly of terthiophene derivatives and flavonoids from Dyssodia species. Terthiophenes are known as photosensitizers by their capacity to generate singlet oxygen (1 O2 ), and flavonoid antioxidant activity is recognized. These opposite properties could represent interesting options in photodynamic therapy. OBJECTIVE: To determine the antioxidant and photosensitizer activities of extracts and isolates of Dyssodia pinnata by electron paramagnetic resonance (EPR). METHODOLOGY: Extracts and isolates were evaluated as antioxidants by the interactions with copper ion (Cu2+ ) observed in EPR, and by the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and the thiobarbituric reactive substances (TBARS) methods. Their abilities as 1 O2 producers were also estimated by EPR. RESULTS: Terthiophenes were obtained from hexane (DPH) and acetone (DPA) extracts, and flavonoids from DPA and methanol (DPM) extracts. The interaction with Cu2+ of extracts and isolated compounds of Dyssodia pinnata showed two effects in EPR: reduction and chelation; flavonoids exhibited both effects, while terthiophenes showed only reduction. DPA, DPM, and flavonoids were active in DPPH and TBARS assays. Quercetagetin-7-O-ß-glucoside showed the highest antioxidant and chelating activities, 3-glycosidated flavonoids were less active. Upon irradiation extracts and terthiophenes induced 1 O2 formation. CONCLUSION: Flavonoid reducing activity on Cu2+ and free radical scavenging capacity were related to the number of hydroxy groups and to the conjugation between the B and C rings. All tested flavonols showed a major complex with Cu2+ , with the most probable site of chelation between the 5-hydroxy and 4-oxo groups. Extracts and terthiophene derivatives showed photosensitizer activity. Thus, EPR is useful to evaluate free radical scavenging and pro-oxidant properties.

Labdanes, Withanolides, and Other Constituents from Physalis nicandroides.

Chemical investigation of the aerial parts (except fruits and calixes) of Physalis nicandroides var. attenuata led to the isolation of a series of new labdane-type diterpenoids, including the closely related compounds 1-3, the labdane glucosides 4 and 5, a mixture of the epimeric alcohols 6 and 7, and one labdanetriol, isolated as its tri-O-acetyl derivative 9. In addition, three new withanolides (14-16) and six known compounds were isolated. The structures of these compounds were elucidated by analysis of their spectroscopic data and chemical transformations, and those of compounds 1, 4, and 16 were confirmed by X-ray diffraction analysis of the natural product (1) and of the corresponding acetyl derivatives 4a and 16a. Fourteen of these compounds were assayed for their in vitro inhibitory activity against yeast α-glucosidase and acetylcholinesterase enzymes. The results were negative in both cases, except for compound 3a that marginally inhibited the activity of acetylcholinesterase with an IC50 value of 64.4 µM.

Structure and Absolute Configuration of Abietane Diterpenoids from Salvia clinopodioides: Antioxidant, Antiprotozoal, and Antipropulsive Activities.

The aerial parts of Salvia clinopodioides afforded abietanes 1a, 2a, and 3 (clinopodiolides A-C), two of which possess an unusual lactol moiety at C-19-C-20, together with an icetexane named clinopodiolide D (4a). Their structures were established by spectroscopic means, mainly 1H and 13C NMR, including 1D and 2D homo- and heteronuclear experiments. The antioxidant, antiprotozoal, and antidiarrheal effects of the isolates were evaluated. Compounds 2a and 3 showed better effects than α-tocopherol in the inhibition of lipid peroxidation with IC50 (µM) = 5.9 ± 0.1 and 2.7 ± 0.2, respectively, and moderate activity in the DPPH assay. All tested compounds showed moderate antiamoebic and antigiardial activity, as well as a good antipropulsive effect.

A New Family of Homoleptic Copper Complexes of Curcuminoids: Synthesis, Characterization and Biological Properties.

We report herein the synthesis and crystal structures of five new homoleptic copper complexes of curcuminoids. The scarcity of reports of homoleptic complex structures of curcuminoids is attributed to the lack of crystallinity of such derivatives, and therefore, their characterization by single crystal X-ray diffraction is rare. The ligand design suppressing the phenolic interaction by esterification or etherification has afforded a significant increase in the number of known crystal structures of homoleptic metal complexes of curcuminoids revealing more favorable crystallinity. The crystal structures of the present new copper complexes show four-fold coordination with a square planar geometry. Two polymorphs were found for DiBncOC-Cu when crystallized from DMF. The characterization of these new complexes was carried out using infrared radiation (IR), nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and single crystal X-ray diffraction (SCXRD) and the antioxidant and cytotoxic activity of the obtained complexes was evaluated.

Synthesis of diphenylamine macrocycles and their anti-inflammatory effects.

A collection of fourteen diphenylamine macrocyclic derivatives containing a peptide chain with different substituents was synthesized using a protocol of two Ugi four component reactions (Ugi-4CR) and a Buchwald-Hartwig macrocyclization. Their anti-inflammatory effects were assayed with an ear edema model using 12-O-tetradecanoylphorbol-13-acetate, while the activity of myeloperoxidase was determined to evaluate the index of leukocyte infiltration. Compound 5e had an ID50 of 0.18 µM per ear with a potency higher than that of the reference drugs indomethacin and celecoxib (0.24 and 0.91 µM per ear, respectively). Moreover, the cytotoxicity of the macrocycles was determined in two healthy cell lines, showing a low percentage of toxicity.