Bioactive amides from Glycosmis species

The mechanism of egg production improvement in laying hens before and after molting revealed by transcriptome and metabolome integration

The objective of this research was to examine the effects and underlying mechanisms of forced molting on the laying rate of hens. A total of ninety 500-day-old laying hens were randomly assigned to three groups: a control group (CK), a starvation group (SG), and a recovery group (RG). The study evaluated follicular development in hens and measured the expression levels of antioxidant, lipid, and inflammatory factors in their serum. Additionally, transcriptomic and metabolomic analyses were performed to assess the effects of forced molting on gene expression and metabolic profiles in hens. The findings indicated that forced molting led to an increase of laying rates, a reduction in follicular closure, and a significant rise in the levels of antioxidant enzymes such as GSH, CAT, and SOD, alongside a decrease in MDA levels. Furthermore, there were significant reductions in the blood lipid levels of LDL, HDL, TC, and TG. Additionally, there were notable differences in the inflammatory markers TNF-α, IL-1, and IL-6. The transcriptomic and metabolomic data revealed that forced molting influenced the activation of the PI3K-AKT and mTOR signaling pathways, affecting fatty acid metabolism in laying hens and modulating the expression of associated genes. In conclusion, this study demonstrates that forced molting is an effective strategy for enhancing the laying rate of hens. Furthermore, it provides a valuable theoretical framework for advancing breeding practices aimed at improving egg production.

Synthesis of Substituted -N-(5-((7-Methyl-2-Oxo-2H-Chromen-4-yl)- Methyl)-1,3,4-Thiadiazol-2-yl)-Benzamide Derivatives Using TBTU as Coupling Agent and their Evaluation for Anti Tubercular Activity

Abstract:

Tuberculosis remains a highly infectious disease across the world. In the identification of new antitubercular agents, coumarin clubbed thiadiazole amides have been synthesized and evaluated for in vitro antitubercular activity. Owing to the growing concern of chemicals and their impact on the environment, greener and faster reaction conditions needed to be incorporated. Therefore, we used TBTU as a coupling reagent for efficient and facile synthesis of substituted-N-(5-((7-methyl-2-oxo-2Hchromes- 4-yl)-methyl)-1,3, 4-thiadiazol-2-yl)-benzamide 4a-j with good yields up to 95% in mild reaction conditions. All the synthesized compounds were evaluated in vitro for anti-tubercular activity against the H37Rv strain of M. tuberculosis. Compounds 4c, 4d, and 4f were found active at 12.5 μg/mL against M. tb H37Rv. Electron withdrawing substituents present on aromatic side chains showed promising anti-tubercular activity.

Traditional uses, phytochemistry, pharmacology, toxicology and formulation aspects of Glycosmis species: A systematic review

The present article is a systematic and constructive review of the traditional medicinal uses, chemistry, pharmacology, toxicology, and formulation aspects of Glycosmis species. The genus Glycosmis comprise 51 accepted species broadly distributed in Australia, China, India, and South-East Asia. Traditionally, Glycosmis species are used in folk medicines to treat cancer, anaemia, rheumatism, fever, cough, liver-related problems, skin ailments, intestinal worm infections, wounds, and facial inflammation. This review aims to provide readers with the latest information highlighting chemical constituents isolated from the Glycosmis species, plant parts utilized for their isolation and their pharmacological activities. So far, 307 chemical constituents have been isolated and characterized from different species of the genus Glycosmis; among these constituents, alkaloids, flavonoids, terpenoids, phenolics, and sulphur-containing amides are the major bioactive compounds. Modern pharmacological studies have shown that the crude extracts and compounds isolated from this genus exhibit a broad spectrum of biological activities like anticancer, antimicrobial, anti-inflammatory, antipyretic, antidiabetic, antioxidant, larvicidal, insecticidal, hepatoprotective, wound healing, antiviral, antidiarrheal, and anxiolytic. The carbazole and acridone alkaloids from this genus have shown potential anticancer activity in various in vitro and in vivo studies. Rare scaffolds like dimeric carbazoles, dimeric acridone alkaloids, flavanocoumarins and sulphur-containing amides from this genus need further exploration for their potential bioactivity. This article also briefs about the toxicological screening and discusses various polyherbal and nano formulation aspects of Glycosmis species. Most of the pharmacological studies reported from this genus were carried out in vitro. An in-depth in vivo and toxicology evaluation of the crude extracts and isolated specialized compounds is required to explore the full therapeutic potential of this genus.

Anti-inflammatory and antiproliferative prenylated sulphur-containing amides from the leaves of Glycosmis pentaphylla

Glycosmis pentaphylla (Retz.) DC (Rutaceae) has been traditionally considered as anti-cancer and anti-inflammatory medicine. However, active compounds of sulphur-containing amides remain largely unknown. In the present work, eighteen previously undescribed sulphur-containing amides (1-18) and three known analogues (19-21) were isolated from the leaves of G. pentaphylla. Their structures were elucidated by NMR spectroscopy and mass spectrometry. All isolated prenylated sulphur-containing amides were evaluated for their anti-inflammatory properties together with antiproliferative activities in vivo. Prenylated sulphur-containing amides exhibited significant inhibitory effects against nitric oxide (NO) production stimulated by lipopolysaccharide in mouse macrophage RAW 264.7 cells with the IC₅₀ values ranging from 0.16 ± 0.10 to 16.74 ± 2.81 μM. Meanwhile, sulphur-containing amides also exhibited considerable antiproliferative activities against HepG2 cell line with IC₅₀ values ranging from 7.47 ± 0.91 to 16.23 ± 0.80 μM. These findings enrich and improve the research on the structural diversity and biological activity of sulphur-containing amides and provide phytochemical and pharmacological evidence for the further development and utilization of the leaves of G. pentaphylla in pharmaceutical industry.

Activity of methylgerambullin from Glycosmis species (Rutaceae) against Entamoeba histolytica and Giardia duodenalis in vitro

Entamoeba histolytica and Giardia duodenalis are widespread intestinal protozoan parasites which both spread via cysts that have to be ingested to infect a new host. Their environment, the small intestine for G. duodenalis and the colon for E. histolytica, contains only very limited amounts of oxygen, so both parasites generate energy by fermentation and substrate level phosphorylation rather than by oxidative phosphorylation. They both contain reducing agents able to reduce and activate nitroimidazole drugs such as metronidazole which is the gold standard drug to treat Entamoeba or Giardia infections. Although metronidazole works well in the majority of cases, it has a number of drawbacks. In animal models, the drug has carcinogenic activity, and concerns about a possible teratogenic activity remain. In addition, the treatment of G. duodenalis infections is hampered by emerging metronidazole resistance. Plant-derived drugs play a dominant role in human medicine, therefore we tested the activity of 14 isolated plant compounds belonging to seven different classes in vitro against both parasites. The tests were performed in a new setting in microtiter plates under anaerobic conditions. The compound with the highest activity was methylgerambullin, a sulphur-containing amide found in Glycosmis species of the family Rutaceae with an EC₅₀ of 14.5 μM (6.08 μg/ml) after 24 h treatment for E. histolytica and 14.6 μM (6.14 μg/ml) for G. duodenalis. The compound was successfully synthesised in the laboratory which opens the door for the generation of new derivatives with higher activity.

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Fourteen plant compounds of seven classes were isolated.

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The activity against Entamoeba histolytica and Giardia duodenalis was tested.

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Methylgerambullin had the highest activity against both parasites.

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Methylgerambullin is a sulphur-containing amide from Glycosmis spp. (Citrus plants).

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High cysteine concentrations interfered with methylgerambullin activity.

Analysis of whole chloroplast genomes from the genera of the Clauseneae, the curry tribe (Rutaceae, Citrus family)

The Clauseneae (Aurantioideae, Rutaceae) is a tribe in the Citrus family that, although economically important as it contains the culinary and medicinally-useful curry tree (Bergera koenigii), has been relatively understudied. Due to the recent significant taxonomic changes made to this tribe, a closer inspection of the genetic relationships among its genera has been warranted. Whole genome skimming was used to generate chloroplast genomes from six species, representing each of the four genera (Bergera, Clausena, Glycosmis, Micromelum) in the Clauseneae tribe plus one closely related outgroup (Merrillia), using the published plastome sequence of Citrus sinensis as a reference. Phylogenetically informative character (PIC) data were analyzed using a genome alignment of the seven species, and variability frequency among the species was recorded for each coding and non-coding region, with the regions of highest variability identified for future phylogenetic studies. Non-coding regions exhibited a higher percentage of variable characters as expected, and the phylogenetic markers ycf1, matK, rpoC2, ndhF, trnS-trnG spacer, and trnH-psbA spacer proved to be among the most variable regions. Other markers that are frequently used in phylogenetic studies, e.g. rps16, atpB-rbcL, rps4-trnT, and trnL-trnF, proved to be far less variable. Phylogenetic analyses of the aligned sequences were conducted using Bayesian inference (MrBayes) and Maximum Likelihood (RAxML), yielding highly supported divisions among the four genera.

Antibacterial Compounds from Glycosmis puberula Twigs

The first phytochemical investigation of Glycosmis puberula twigs led to the isolation and identification of a new quinolone alkaloid, glycosmispuberulone (1), along with ten known compounds (2–11). The structures were elucidated by spectroscopic analyses and comparison with previously reported data. Their antibacterial activities against Gram-positive and Gram-negative bacteria were also evaluated.

Acridone alkaloids from Glycosmis chlorosperma as DYRK1A inhibitors

Two new acridone alkaloids, chlorospermines A and B (1 and 2), were isolated from the stem bark of Glycosmis chlorosperma, together with the known atalaphyllidine (3) and acrifoline (4), by means of bioguided isolation using an in vitro enzyme assay against DYRK1A. Acrifoline (4) and to a lesser extent chlorospermine B (2) and atalaphyllidine (3) showed significant inhibiting activity on DYRK1A with IC50's of 0.075, 5.7, and 2.2 μM, respectively. Their selectivity profile was evaluated against a panel of various kinases, and molecular docking calculations provided structural details for the interaction between these compounds and DYRK1A.

Alkamid database: Chemistry, occurrence and functionality of plant N-alkylamides

ETHNOPHARMACOLOGICAL RELEVANCE

N-Alkylamides (NAAs) are a promising group of bioactive compounds, which are anticipated to act as important lead compounds for plant protection and biocidal products, functional food, cosmeceuticals and drugs in the next decennia. These molecules, currently found in more than 25 plant families and with a wide structural diversity, exert a variety of biological-pharmacological effects and are of high ethnopharmacological importance. However, information is scattered in literature, with different, often unstandardized, pharmacological methodologies being used. Therefore, a comprehensive NAA database (acronym: Alkamid) was constructed to collect the available structural and functional NAA data, linked to their occurrence in plants (family, tribe, species, genus).

MATERIALS AND METHODS

For loading information in the database, literature data was gathered over the period 1950-2010, by using several search engines. In order to represent the collected information about NAAs, the plants in which they occur and the functionalities for which they have been examined, a relational database is constructed and implemented on a MySQL back-end.

RESULTS

The database is supported by describing the NAA plant-, functional- and chemical-space. The chemical space includes a NAA classification, according to their fatty acid and amine structures.

CONCLUSIONS

The Alkamid database (publicly available on the website http://alkamid.ugent.be/) is not only a central information point, but can also function as a useful tool to prioritize the NAA choice in the evaluation of their functionality, to perform data mining leading to quantitative structure-property relationships (QSPRs), functionality comparisons, clustering, plant biochemistry and taxonomic evaluations.

Two new acridone alkaloids from Glycosmis macrantha

Extraction and chromatographic separation of the extracts of dried stem barks of Glycosmis macrantha lead to isolation of two new acridone alkaloids, macranthanine (1) and 7-hydroxynoracronycine (2), and a known acridone, atalaphyllidine (3). The structures of these alkaloids were determined by detailed spectral analysis and also by comparison with reported data.

Anti-leishmanial activity of plant-derived acridones, flavaglines, and sulfur-containing amides

Visceral and cutaneous leishmaniases are an important public health problem in endemic geographic regions in 88 countries worldwide, with around 12 million infected people. Treatment options are limited due to toxicity and teratogenicity of the available drugs, response problems in HIV/Leishmania co-infections, and upcoming resistances. In this study, we investigated the anti-leishmanial activity of 13 plant-derived compounds in vitro aiming to find new drug candidates. Toxicity of the compounds was evaluated in human primary hepatocytes, and hemolytic activity was examined in freshly isolated erythrocytes. Two acridones, 5-hydroxynoracronycine and yukocitrine, two flavaglines, aglafoline and rocaglamide, and the sulfur-containing amide methyldambullin showed promising anti-leishmanial activities with 50% effective concentrations (EC50s) of 34.84, 29.76, 7.45, 16.45, and 6.29 μM, respectively. Hepatotoxic activities of 5-hydroxynoracronycine, yukocitrine, and methyldambullin were significantly lower compared to miltefosine and lower or equal compared to artesunate, whereas the ones of rocaglamide and aglafoline were slightly higher compared to miltefosine and significantly higher compared to artesunate. None of the compounds showed hemolytic activity.

High antitrypanosomal activity of plant-derived sulphur-containing amides

Chagas disease, caused by Trypanosoma cruzi, represents an important public health problem in endemic geographic regions in Middle and South America, affecting 15 million infected people. Treatment options are still limited due to the toxicity of available drugs, parasite resistance and poor drug activity during the chronic phase of the disease. In this study, we investigated the in vitro antitrypanosomal activity of 15 tropical plant-derived compounds with the aim of finding new drug candidates. Three novel sulphur-containing amides (methyldambullin, methylgerambullin and sakambullin) showed promising antitrypanosomal activities, with 50% effective concentrations (EC₅₀ values) after 72 h exposure of 1.7, 1.23 and 5.18 μM, respectively, compared with EC₅₀ values for amphotericin B and benznidazole of 0.71 μM and 30.89 μM, respectively.

Alcoholysis of naturally occurring imides: misleading interpretation of antifungal activities

The frequent presence of the sulfur-containing amide penangin (10) in leaf extracts of Glycosmis species turned out to be the result of decomposition of imides generated by extraction and storage in MeOH. Reinvestigation of Glycosmis mauritiana and G. cf. puberula with acetone revealed the presence of six imides. In addition to penimides A (1) and B (2) and ritigalin (6), three new derivatives, krabin (4), isokrabin (5), and methoxypenimide B (3), were isolated and identified by spectroscopic methods. All six imides were shown to be susceptible to different rates of methanolic cleavage, leading to their corresponding methyl esters and sulfur-containing amides. Whereas the decomposition products penangin (10), isopenangin (11), and sinharin (14) are known, the corresponding cleavage of methyl N-methylthiocarbamate (7) from ritigalin (6), monitored in situ by (1)H NMR spectroscopy, is described here for the first time. Its structure was further confirmed by GC-MS coupling. HPLC-UV comparison of many different samples of G. mauritiana, extracted with MeOH, revealed considerable chemical variations in sulfur-containing amides, strongly correlated with different antifungal potency. The lack of activity of many methanolic crude extracts can be explained by a preponderance of the inactive decomposition product penangin (10), whereas the corresponding naturally occurring imides penimides A (1) and B (2) and methoxypenimide B (3), extracted with acetone, showed high fungitoxic properties.

Prenylated flavanones and flavanonols as chemical markers in Glycosmis species (Rutaceae)

Fifteen prenylated or geranylated flavanones and flavanonols were isolated from the leaf extracts of different Glycosmis species collected in Thailand and Malaysia. All structures were elucidated by spectroscopic methods, especially 1D and 2D NMR. Six compounds were described for the first time and two were only known so far as synthetic products. The chemotaxonomic significance of flavanoid accumulation within the genus Glycosmis is highlighted.

Fungistatic and bacteriostatic activities of alkamides from Heliopsis longipes roots: affinin and reduced amides

This work demonstrates the fungistatic and bacteriostatic activities of affinin, the main alkamide of Heliopsis longipes (Gray) Blake (Asteraceae) roots and two alkamides obtained by catalytic reduction of affinin: N-isobutyl-2E-decenamide and N-isobutyl-decanamide. The bioactivity was tested against Rhizoctonia solani groups AG3 and AG5, Sclerotium rolfsii, Sclerotium cepivorum, Fusarium sp., Vertcillium sp., phytopathogenic fungi; Phytophthora infestans, a phytopathogenic Chromista; Saccharomyces cerevisiae, a nonphytopathogenic ascomycete; and Escherichia coli, Erwinia carotovora, and Bacillus subtilis, bacteria. Affinin, being the primary component of the lipidic fraction, is expected to be responsible for the fungitoxic activity observed in roots of this plant species. Four of the assayed fungi showed an important sensitivity to the presence of affinin: S. rolfsii, S. cepivorum, P. infestans, and R. solani AG-3 and AG-5, displaying a growth inhibition of 100%. S. cerevisiaeshowed a similar growth inhibition with affinin. None of the alkamides obtained by catalytic reduction of affinin showed a fungitoxic activity. Affinin had a definite negative effect on the growth of E. coli and B. subtilis, but E. carotovora carotovora was not sensitive to the highest dose of affinin assayed. N-Isobutyl-2E-decenamide displayed a higher bacteriostatic activity against E. coli and E. carotovora carotovora. In both cases, this alkamide was more potent than affinin. On the other hand, only N-isobutyl-decanamide displayed a significant activity on the growth of B. subtilis.

A new flavonoid and Sulphur-containing amides fromGlycosmis Chlorosperma

A new flavonoid, dihydroglychalcone-A, was isolated from the leaves extract of Glycosmis chlorosperma in addition to two known sulphur-containing amides, dambullin and gerambullin. The structure of the new compound was assigned as 2'-hydroxy-4,6'-dimethoxy-3',4'-(2",2"-dimethylpyrano)dihydrochalcone. The extract of the leaves was also found to exhibit antimicrobial and cytotoxic activities.

Stress induced carbazole phytoalexins in Glycosmis species

Induced formation of a series of carbazole alkaloids was observed in leaves of Glycosmis parviflora and G. pentaphylla after wounding, UV-irradiation, and particularly after inoculation with the fungus Botrytis cinerea. Chemical variation between different provenances and even individuals of G. parviflora led to an accumulation of different derivatives from which three proved to be undescribed natural products. Their structures were identified by spectroscopic methods and named carbalexins A, B, and C. Bioautographic tests on TLC plates with Cladosporium herbarum exhibited strong antifungal activity for the new carbalexins as well as for the already known 2-hydroxy-3-methylcarbazole, but only weak effects for the pyranocarbazole glycoborinine. Detailed experiments with marked infection areas confirmed the restricted accumulation of carbazole derivatives which could not be detected in non-infected areas of the same leaf. Apart from carbazoles, in some individuals of G. parviflora an additional accumulation of the pyranoquinolones flindersine and methylflindersine was induced, which supports the already previously discussed biogenetic connections between carbazoles and prenylated quinolones.

Dehydrothalebanin: a source of resistance from Glycosmis pentaphylla against the citrus root weevil Diaprepes abbreviatus

Roots of a citrus relative, Glycosmis pentaphylla (orangeberry), were shown to inhibit the growth and survival of larvae of the citrus root weevil Diaprepes abbreviatus. Roots of G. pentaphyllaincorporated into the diet of D. abbreviatus increasingly inhibited the growth of neonate larvae with increased concentration of roots, while roots from citrus rootstocks produced little inhibition. The diet-incorporation assay was used to guide fractionation of an active acetone extract of G.pentaphylla roots. Three major fractions from silica open-column liquid chromatography were active, and these were purified using semipreparative normal-phase HPLC. A single active HPLC subfraction was isolated from each of the three liquid chromatography fractions, and two active compounds were isolated and identified by GC-MSD. GC-MSD and NMR identified one compound as the amide dehydrothalebanin B, and the other was identified by GC-MSD as dieldrin, a chlorinated hydrocarbon insecticide whose origin in our samples is uncertain.

Prenylated sulfonyl amides from Glycosmis species

Nine new sulfur containing amides were isolated from the lipophilic leaf extracts of different varieties of Glycosmis chlorosperma and G. ex aff. pseudoracemosa mainly collected in Thailand. Their structures were elucidated by spectroscopic methods. All amides were shown to be characterized by a methylsulfonylpropenoic acid moiety linked to a p-geranyloxy- or p-prenyloxy-phenethylamide rest. The compounds differ by different states of oxidation (i) at the 2-position of the ethylamine unit, (ii) at the aromatic m-position of phenethylamine, or (iii) at the terminal methyl group of the geranyloxy side chain.

Infraspecific variation of sulfur-containing bisamides from Aglaia leptantha

Six new amides, leptaglin (1), hemileptaglin (2), aglanthin (3), agleptin (4), isoagleptin (5), and leptanthin (6), together with known lignans yangambin, eudesmin, grandisin (7), epigrandisin (8), and dehydrodiconiferyl alcohol, were isolated and identified from the lipophilic leaf and stem bark extracts of Aglaia leptantha. The dominating sulfur-containing bisamides contained either putrescine or the corresponding pyrrolidine ring as the diamine part, linked to phenylacetic and/or methylthiopropenoic acid moieties showing a remarkable infraspecific variation in eight individuals from two different habitats. Structures were determined by MS and NMR, including lanthanide-induced shifts.

Cyclopenta[b]benzofurans from Aglaia species with pronounced antifungal activity against rice blast fungus (Pyricularia grisea)

Eight flavaglines, six cyclopenta[b]benzofurans, a cyclopenta[bc]benzopyran, and a benzo[b]oxepine, together with an aromatic butyrolactone were isolated from Aglaia odorata, A. elaeagnoidea, and A. edulis (Meliaceae) and tested against the three plant pathogens Pyricularia grisea, Fusarium avenaceum, and Alternaria citri for antifungal properties. Using the microdilution technique linked with digital image analysis of germ tubes, the benzofurans displayed strong activity, whereas the benzopyran, benzoxepine, and butyrolactone were inactive at the highest concentration tested. P. grisea, responsible for rice blast disease, was the most susceptible fungus against all benzofurans, with rocaglaol as the most active derivative. Based on EC(50), EC(90), and MIC values, the antifungal activity of rocaglaol was clearly higher than of the reference compounds, blasticidin S and Benlate.

Antimicrobial properties of alkamides present in flavouring plants traditionally used in Mesoamerica: affinin and capsaicin

The bioactive amides affinin and capsaicin isolated respectively from Heliopsis longipes roots and Capsicum spp fruits, were assayed for activity against Escherichia coli, Pseudomonas solanacearum, Bacillus subtilis and Saccharomyces cerevisicae suspension cultures. The alkamide affinin inhibited growth of E. coli and S. cerevisiae at concentrations as low as 25 microg/ml. Higher concentrations of affinin were necessary to inhibit growth of P. solanacearum and B. subtilis. However. high concentrations of capsaicin only retarded the growth of E. coli and P. solanacearum, whereas growth of B. subtilis was strongly inhibited and that of S. cerevisiae was initially enhanced. Results are discussed in relation to previous reports concerning crude extract and to the molecular structures of the bioactive compounds.

Bisamides, lignans, triterpenes, and insecticidal Cyclopenta[b]benzofurans from Aglaia species

Twelve new derivatives of bisamides [piriferinol (5), edulimide (7)], lignans [lariciresinol acetat (10)], triterpenes [4-bis-norcycloartane-type triterpenes (11a, 12a+b, 13a+b)], cyclopenta[b]benzofurans [pannellin (15), pannellin 1-O-acetate (16), 3'-methoxypannellin (17)], and an aromatic butyrolactone [aglalactone (18)] were isolated and identified from lipophilic leaf, stem, and root extracts of Aglaia spp. elaeagnoidea, edulis, grandis, silvestris, and tomentosa. Two cyclopenta[b]benzofurans (flavaglines), pannellin (15) and pannellin 1-O-acetate (16), displayed very strong insecticidal activity against Spodoptera littoralis and Lymantria dispar, comparable with the activity of azadirachtin.

Prenylated phenylpropenes from Coleonema pulchellum with antimicrobial activity

The lipophilic root extract of Coleonema pulchellum was analysed and tested for antifungal and antibacterial activity. Eight previously undescribed prenyloxy and geranyloxy phenylpropenes, were isolated as major compounds together with the known evofolin-C as well as the lignans (+/-)-sesamin and (+/-)-prenylpiperitol, the diterpene (-)-pimara-9(11),15-dien-19-oic acid and the 2,4-decadienoic acid isobutylamide. All structures were established by spectroscopic evidence. From the new phenylpropenes, named evofolin-C-acetate, colenemol, colenemal, prenycol acetate, dehydroprenycol acetate, precolpuchol, colpuchol and colpuchol acetate, the dihydroxylated precolpuchol displayed the strongest antifungal and antibacterial activity against Cladosporium herbarum and Staphylococcus aureus, respectively.