Search

Five new alkaloids, hirsutellones A–E, were isolated from the insect pathogenic fungus Hirsutella nivea BCC 2594. Their structures were elucidated by spectroscopic analysis and X-ray crystallography. Hirsutellones displayed significant growth inhibitory activity against Mycobacterium tuberculosis H37Ra.

Four new cyclohexadepsipeptides, enniatins L (1), M1 (2), M2 (3), and N (4), have been isolated from an unidentified fungus (BCC 2629), together with the known enniatins B (5), H (6), and I (7), MK1688 (8), and enniatin B4 (9). Compounds 1–4 are the first enniatin analogs with an OH group at the side chain of one of the 2-hydroxycarboxylic acid residues. The structures of 1–4 were elucidated by spectroscopic means and by X-ray crystallography.

One-pot reactions between ortho-dihydroxyarenes with 1,2-diols or dithiols in the presence of p-toluenesulfonic acid yielded the corresponding dioxins or dithiins in good to excellent yields.

Aigialone (1) and aigialospirol (2), two structurally unique compounds, were isolated from the mangrove fungus Aigialus parvus BCC 5311. The structure of the new ketene acetal 1 was elucidated by spectral analysis, and its relative stereochemistry was determined by X-ray crystallography. The stereochemistry of aigialospirol (2), elucidated by NMR spectral analysis, suggested that this compound is possibly derived from hypothemycin (3), a metabolite previously isolated from this same fungus.

Two new antimycobacterial dibenzo[b,f]oxepins, bauhinoxepins A (=3,3,5-trimethylbenzo[b]pyrano[g][1]benzoxepin-6,11-diol; 1) and B (=6-methoxy-7-methyl-2-(3-methylbut-2-enyl)dibenzo[b,f]oxepine-1,8-diol; 2), were isolated from the roots of Bauhinia saccocalyx, and their structures were elucidated by analysis of spectroscopic data. Bauhinoxepins A and B exhibited antimycobacterial activities with respective minimum-inhibitory concentrations (MIC) of 6.25 and 12.5 μg/ml. They were inactive (at 20 μg/ml) against the malarial parasite, and also inactive (at 20 μg/ml) towards the Vero, KB, and BC cell lines.

Deprotonation of an oxiranyl β-proton takes place in a stereoselective manner providing the corresponding oxiranyl ‘remote’ anion. The anion is stabilized by chelation between the lithium and the carbonyl moiety of an ester, lactone, imide, or keto-group in the form of a five-membered cyclic intermediate. Certain ester-stabilized oxiranyl anions are stable and can be left in THF solution at −78°C for several hours. The generated anions undergo a stereoselective alkylation reaction to provide products, which could be useful intermediates in the synthesis of bioactive naturally occurring α-methylene bis-γ-butyrolactones.

Two new enniatins H ( 3 ) and I ( 4 ), whose substituents on 2-hydroxycarboxylic acid moieties were different from those of known compounds, were isolated, together with known enniatins B ( 1 ) and B 4 ( 2 ), from the insect pathogenic fungus Verticillium hemipterigenum BCC 1449. Structures of these compounds were elucidated by spectroscopic means. Studies on precursor-directed biosynthesis with strain BCC 1449 led to the production and identification of three analogs, enniatins G ( 5 ), C ( 6 ) and MK1688 ( 7 ), as well as the stereochemical elucidation of 3 and 4 . Enniatins 1 – 7 were evaluated for their antiplasmodial and antimycobacterial activities.

Precursor-directed biosynthesis of beauvericin analogs, cyclohexadepsipeptide antibiotics, was investigated using the insect pathogenic fungus Paecilomyces tenuipes BCC 1614. Feeding l -isoleucine or d -alloisoleucine in liquid medium led to the enhanced production of beauvericin A and beauvericin B together with beauvericin and a missing analog, beauvericin C. Feeding experiments with d -isoleucine or l -alloisoleucine resulted in the production of diastereomers of beauvericins A, B and C, named allobeauvericins A, B and C, respectively.

Nucleophilic additions of lithium keto and ester enolates and mono- and bifunctional Grignard reagents to artemisitene provided C-16-derived artemisinin monomers, dimers, trimers, and tetramers whose antimalarial and cytotoxic activities have been evaluated.

Three known compounds, 2-hexylidene-3-methylsuccinic acid (1), cytochalasin Q (2), and 5-carboxymellein (3), together with two new derivatives, 2-hexylidene-3-methylsuccinic acid 4-methyl ester (4) and an ophiobolane sesterterpene named halorosellinic acid (5), were isolated from culture broth of the marine fungus Halorosellinia oceanica BCC 5149. Compounds 1-3 exhibited moderate cytotoxicity against KB and BC-1 cell lines with IC(50) values of 1-13 microg/mL, while compounds 2, 3, 5, and 6 showed antimalarial activity with respective IC(50) values of 17, 4, 13, and 19 microg/mL. Halorosellinic acid (5) possessed only weak antimycobacterial activity with the minimum inhibitory concentration of 200 microg/mL.

Phomoxanthones A (1) and B (2), two novel xanthone dimers, were isolated from the endophytic fungus Phomopsis sp. BCC 1323. Structures of 1 and 2 were elucidated by spectroscopic methods. These compounds exhibited significant in vitro antimalarial and antitubercular activities and cytotoxicity.

Cordyanhydrides A and B, two new alkenoic acids bearing two and three maleic anhydride moieties in the linear acid chain, were isolated and identified from a culture broth of the insect pathogenic fungus Cordyceps pseudomilitaris BCC 1620.

The syntheses of α-methylene γ-butyrolactones and α-methylene bis-γ-butyrolactones are made simple through the use of the versatile dimethyl itaconate - anthracene adduct, 1 .

Directed by substituent R1, the α-allyl-γ-butyrolactone 9 either undergoes cyclisation to give the alcoholic cyclopentenone 12 or 1,2-acyl migration to give 13, when subjected to treatment with LDA in THF/TMEDA. An effective strategy to nullify this directive influence, and dictate cyclisation, is exemplified in a model synthesis of spiro[4,5]dec-2-ene-1,6-dione 19 by a one-pot tandem cyclisation — elimination process starting from 16.

Two known spirodihydrobenzofuran terpenes (1 and 2) were isolated from a mycelium extract of the fungus Stachybotrys nephrospora BCC 3900. Compound 1 (Mer-NF5003F or stachybotrydial) exhibited potent antiviral activity (the IC50 value of 4.32 microg/mL) comparable to the standard drug, acyclovir, while compound 2 was inactive against the HSV-1 virus. Both 1 and 2 possessed antiplasmodial activity (IC50 values of 0.85 and 0.15 microg/mL for 1 and 2, respectively), and were not toxic towards the Vero cell line. A regiospecific conversion of the dialdehyde 1 to the lactone 2 proceeded simply under acidic conditions.

Bisalkylthioarenes can be prepared efficiently from reactions between dihydroxyarenes and thiols under acidic conditions.

Various derivatives of artemisinin covalently linked to iron chelators were synthesized, and their antimalarial activities were evaluated. Although results show no indication that the presence of an iron chelator in the vicinity of artemisinin potentiates its action, the linked compounds prepared still retain comparable activities to that of artemisinin.

Several terpenes, including the novel diterpene peroxide (5) with potent activity against Plasmodium falciparum, have been isolated from Amomum krervanh (“cardamom”).

Two new pimarane diterpenes, diaportheins A (1) and B (2), were isolated from a culture broth of the fungus Diaporthe sp. BCC 6140. Diaporthein B (2) strongly inhibited the growth of Mycobacterium tuberculosis with the MIC value of 3.1 microg/mL, while diaporthein A (1) showed only mild activity (MIC value of 200 microg/mL).

Spiro[4.4]non- and spiro[4.5]dec-2-ene-1,6-diones [2; n = 0 and 1] were prepared in moderate to high enantiomeric purities via asymmetric allylation of enamines 6 and ketal derivatives 7 and 8 formed from keto-esters 5, followed by a carbanionic cyclization process.

A new cyclohexadepsipeptide, named hirsutellide A (1), was isolated from a cell extract of the entomopathogenic fungus Hirsutella kobayasii BCC 1660. The structure of 1 was elucidated by analyses of spectroscopic data, and its absolute stereochemistry was addressed by the use of Marfey's method. Hirsutellide A (1) exhibited antimycobacterial and antimalarial activities, but was inactive toward the Vero cell line (at 50 microg/mL).

Bioassay-guided fractionation of the cell extract of the insect pathogenic fungus Aschersonia tubulata BCC 1785 led to the isolation of dustanin (1), 3 beta,15 alpha,22-trihydroxyhopane (3), 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-diene-3 beta-ol (6), together with the new 3 beta-acetoxy-15 alpha,22-dihydroxyhopane (4). Chemical structures of these compounds were elucidated by spectral analyses as well as chemical transformation. Compounds 1 and 4 exhibited antimycobacterial activity with the minimum inhibitory concentration (MIC) of 12.5 micrograms/ml.

Activity guided fractionation of extracts from Clausena harmandiana have led to the identification of four known compounds, heptaphylline (1), clausine K (2), dentatin (5), and clausarin (6). All these compounds, except clausine K (2), exhibited antiplasmodial activity against Plasmodium falciparum. While the new dimethylated derivative 4, derived from 2, showed no antiplasmodial activity, the monomethylated product 3 (clausine H) exhibited activity comparable to that observed for compounds 1 and 5.

Bioassay-guided fractionation of the extract from the wood-decayed fungus Xylaria sp. BCC 1067 led to the isolation of five antiplasmodial compounds, (-)-depudecin, (+)-phaseolinone, (+)-phomenone, 19,20-epoxycytochalasin Q, and (E)-methyl 3-(4-methoxyphenoxy)propenoate. These structures were elucidated using spectroscopic methods, especially NMR analysis.

Three new glycosidic antibiotics, glykenin (GK)-III A, B, and C (2a-c), were isolated as a mixture from a strain of Basidiomycetes sp. and identified as glycosides of C26-fatty acids and a diacetylated trisaccharide composed of glucose and two xyloses. The locations of the two acetyl groups were elucidated by secondary ion mass spectrometry (SIMS), double quantum filter (DQF), and relayed chemical shift correlation spectroscopy (COSY) spectral analysis.

The structures of three aglycones of glykenins, produced by Basidiomycetes sp., were determined to be (2S, 16R, 17S, 21R)-2, 16, 17, 21-, (2S, 17R, 18S, 22R)-2, 17, 18, 22-, and (2S, 17S, 18S, 22R)-2, 17, 18, 22-tetrahydroxyhexacosanoic acids (3a-c). The absolute configurations of two of the four hydroxy groups in 3a-c were established by chiral synthesis of the degradation products (6a-c and 7a-c). Chemical transformation of 3a-c to 6, 8-dioxabicyclo[3.2.1]octane derivatives (18-c) revealed the relative and absolute configurations of the acyclic 1, 2-diol moieties in 3a-c.

Bioassay-guided fractionation of an extract from the fungus Myrothecium verrucaria BCC 112 resulted in the first isolation of roridin E acetate (5) from nature together with four common macrocyclic trichothecene isomers (1-4). Trichothecenes 1-5, while known as mycotoxins, were evaluated for their high antimalarial activity.

Chemical exploration of Camchaya calcarea (family Compositae) has led to the isolation of nine known sesquiterpene lactones 1 - 9, together with caffeic acid methyl ester 10. Sesquiterpenes 1, 2, 3, 4, 5, 7, and 8 exhibited moderate antiplasmodial activity, but showed potent antimycobacterial activity. Interestingly, the cytotoxicity of sesquiterpene lactones 1, 2, and 4 towards small-cell lung cancer cell line (NCI-H187) is stronger (two orders of magnitude) than towards the Vero cell line. Caffeic acid methyl ester (10) was cytotoxic against NCI-H187 and BC cell lines, however the ester 10 showed only mild antimycobacterial activity.

Eight new compounds (2-9), together with a known dithiodiketopiperazine (1), were isolated from the seed fungus Menisporopsis theobromae BCC 3975. The structures of these substances were elucidated by analyses of spectroscopic data. Compounds 1 and 4 exhibited moderate cytotoxicity against BC-1 cell lines with IC50 values of 29.2 and 57.4 microM, respectively. Cytotoxicity of 1, 2, 4, and 9 against the NCI-H187 cell line showed respective IC50 values of 22.9, 20.3, 1.8, and 56.6 microM. Compounds 2 and 4 exhibited antimalarial activity with IC50 values of 2.95 and 28.8 microM, respectively. Substances 1, 4, 7, 8, and 9 possessed weak antimycobacterial activity (MIC 154.8-952.3 microM), while compounds 2 and 3 showed potent antimycobacterial activity with respective MIC values of 1.24 and 7.14 microM.

Optimal fermentation conditions for enniatin production using the entomopathogenic fungus Verticillium hemipterigenum BCC 1449 have been investigated. Among various liquid media tested, highest efficiency of enniatin production was achieved by fermentation in yeast extract sucrose. Application of this condition to large-scale fermentation resulted in the isolation of three new analogs, O1, O2 and O3, which are closely related isomers that were characterized as an inseparable mixture, along with seven known enniatins.

Chemical investigation of biologically active compounds of Getonia floribunda led to the isolation of two new macrocyclic lactones, combretastatins D-3 (1) and D-4 (2). The structures of these compounds were confirmed by spectroscopic analyses. Combretastatin D-3 (1) exhibited cytotoxicity towards the small-cell lung cancer cell line (NCI-H187, IC50=13.0 +/- 0.2 microg/mL) but was inactive against KB, BC-1, and Vero cell lines. Combretastatin D-3 (1) showed weak antitubercular activity with a minimum inhibitory concentration (MIC) of 100.0 microg/mL, and was inactive towards the malarial parasite. Combretastatin D-4 (2) was inactive in all antitubercular, antiplasmodial, and cytotoxic assays.

An antimalarial macrocyclic polylactone, menisporopsin A (1), was isolated from a cell extract of the seed fungus Menisporopsis theobromae. The structure of 1 was elucidated on the basis of spectroscopic analysis and chemical transformations, with the absolute configuration established by application of the modified Mosher method and by using chiral HPLC. Menisporopsin A (1) possesses an unprecedented residue, 2,4-dihydroxy-6-(2,4-dihydroxy-n-pentyl)benzoic acid. This compound exhibited antimalarial activity, with an IC(50) value of 4.0 microg mL(-1), and antimycobacterial activity (MIC value of 50 microg mL(-1)).

Vertihemipterin A, the ascochlorin glycoside, and its aglycone, 4',5'-dihydro-4'-hydroxyascochlorin, were isolated from the insect pathogenic fungus Verticillium hemipterigenum BCC 2370. A new analog, 8'-hydroxyascochlorin, and five known compounds, ascochlorin, LL-Z1272delta, 8',9'-dehydroascochlorin, ascofuranone and ascofuranol, were also isolated from the same fermentation broth. Structures of these compounds were elucidated by spectroscopic methods. Stereochemistry of the known compound, 4',5'-dihydro-4'-hydroxyascochlorin, was addressed by NMR spectral analyses and the modified Mosher's method. Antiviral (HSV-1) and cytotoxic activities of these ascochlorin analogs were evaluated.

The resistance to pyrimethamine (PYR) of Plasmodium falciparum arising from mutation at position 108 of dihydrofolate reductase (pfDHFR) from serine to asparagine (S108N) is due to steric interaction between the bulky side chain of N108 and Cl atom of the 5-p-Cl aryl group of PYR, which consequently resulted in the reduction in binding affinity between the enzyme and inhibitor. Molecular modeling suggested that the flexible antifolate, such as trimethoprim (TMP) derivatives, could avoid this steric constraint and should be considered as new, potentially effective compounds. The hydrophobic interaction between the side chain of inhibitor and the active site of the enzyme around position 108 was enhanced by the introduction of a longer and more hydrophobic side chain on TMP's 5-benzyl moiety. The prepared compounds, especially those bearing aromatic substituents, exhibited better binding affinities to both wild type and mutant enzymes than the parent compound. Binding affinities of these compounds correlated well with their antimalarial activities against both wild type and resistant parasites. Molecular modeling of the binding of such compounds with pfDHFR also supported the experimental data and clearly showed that aromatic substituents play an important role in enhancing binding affinity. In addition, some compounds with 6-alkyl substituents showed relatively less decrease in binding constants with the mutant enzymes and relatively good antimalarial activities against the parasites bearing the mutant enzymes.

Two new diketopiperazines, bisdethiodi (methylthio)-1-demethylhyalodendrin and 1-demethylhyalodendrin tetrasulfide, together with two known cyclodepsipeptides, enniatins B and B4, and two known pyrones, pyrenocines A and B, were isolated from a culture broth of the entomopathogenic fungus Verticillium hemipterigenum BCC 1449. These structures were elucidated using spectroscopic methods and X-ray crystallography. Antimalarial and cytotoxic activities of these compounds were evaluated.

Two new 8,9-secokaurane diterpenes, ent-8,9-seco-7alpha,11beta-diacetoxykaura-8(14),16-dien-9,15-dione (1) and ent-8,9-seco-8,14-epoxy-7alpha-hydroxy-11beta-acetoxy-16-kauren-9,15-dione (2), together with two known compounds, ent-8,9-seco-7alpha-hydroxy-11beta-acetoxykaura-8(14),16-dien-9,15-dione (3) and ent-7beta-hydroxy-15-oxokaur-16-en-18-yl acetate, were isolated from Croton kongensis. This is the first report on the presence of 8,9-secokauranes in the plant genus Croton. Diterpenes 1-3 exhibited antimycobacterial activity with minimum inhibitory concentrations (MICs) of 25.0, 6.25, and 6.25 microg/mL, respectively, and possessed antimalarial activity with IC(50) ranges of 1.0-2.8 microg/mL. They also demonstrated comparable cytotoxicity toward the Vero (IC(50) ranged from 0.9 to 3.2 microg/mL), KB (IC(50) from 1.2 to 13.8 microg/mL), and BC cell lines (IC(50) from 1.1 to 2.2 microg/mL, except for compound 1, which was inactive against BC cells).

Derivatives of ethyl 5-phenyl-6-oxa-1-azabicyclo[3.1.0]hexane-2-carboxylate (14-20), with side chains varying from three to five carbon atoms and bearing various substituents, have been prepared from ethyl 2-phenyl-1-pyrroline-5-carboxylate (12). Their in vitro activity against P. falciparum (K1 strain) and antimycobacterium and also their cytotoxic activity against Vero cell have been evaluated.

A novel secondary metabolite, pughiinin A, together with pycnidione, mevalonolactone, and 7-hydroxy-2-methylchromanone, was isolated from the seed fungus Kionochaeta pughii BCC 3878. The chemical structure was established by spectroscopic methods and by single crystal X-ray crystallography. Pughiinin A and pycnidione exhibited in vitro antiplasmodial activity against Plasmodium falciparum (K1 strain). Pycnidione also showed anti-cancer activity against KB and BC cell lines with the IC 50 values of 2.0 and 1.6 microg/mL, respectively.

The reduced binding of pyrimethamine to Ser108Asn (S108N) mutants of parasite dihydrofolate reductase (DHFR), which forms the basis of resistance of Plasmodium falciparum to pyrimethamine, is largely due to steric constraint imposed by the bulky side chain of N108 on Cl of the 5-p-Cl-phenyl group. This and other S108 mutants with bulky side chains all showed reduced binding to pyrimethamine and cycloguanil. Less effect on binding to some bulky mutants was observed for trimethoprim, with greater flexibility for the 5-substituent. S108N DHFR also binds poorly with other pyrimethamine derivatives with bulky groups in place of the p-Cl, and the binding was generally progressively poorer for the double (C59R+S108N) mutant. Removal of the p-Cl or replacement with m-Cl led to better binding with the mutant DHFRs. Pyrimethamine analogues with unbranched hydrophobic 6-substituents showed generally good binding with the mutant DHFRs. A number of compounds were identified with high affinities for both wild-type and mutant DHFRs, with very low to no affinity to human DHFR. Some of these compounds show good antimalarial activities against pyrimethamine-resistant P. falciparum containing the mutant DHFRs with low cytotoxicity to three mammalian cell lines.

A new preussomerin isomer, 3'-O-demethylpreussomerin I, five known preussomerins E - I, and two known deoxypreussomerins, deoxypreussomerin A and bipendensin (palmarumycin C11), were isolated from a lichenicolous fungus Microsphaeropsis sp. BCC 3050. These structures were elucidated by spectroscopic methods, especially 1D- and 2D-NMR. The preussomerins were evaluated for their antimycobacterial and antiplasmodial activities as well as cytotoxicity against KB, BC-1 and vero cell lines.

Two new 10-membered lactones, namely, multiplolides A (1) and B (2), were isolated from the broth extract of the fungus Xylaria multiplex BCC 1111. Chemical structures of 1 and 2 were elucidated on the basis of their spectral data. Multiplolides A (1) and B (2) exhibited antifungal activity against Candida albicans with IC(50) values of 7 and 2 microg/mL, respectively. Both 1 and 2 were inactive in the screening systems toward the malarial parasite Plasmodium falciparum (at 20 microg/mL) and were not cytotoxic to BC-1 and KB cell lines (at 20 microg/mL).

New furanoid labdane diterpenes, potamogetonyde (3) and potamogetonol (4), together with two known compounds, potamogetonin (1) and 15,16-epoxy-12-oxo-8(17),13(16),14-labdatrien-20,19-olide (2), were isolated from the CH(2)Cl(2) extract of Potamogeton malaianus. The chemical structures of 1-4 were elucidated by the analyses of their spectral data, mainly by 1D and 2D NMR techniques. Potamogetonyde (3) and potamogetonol (4) exhibited potent antiviral (HSV-1) activity with respective IC(50) values of 8 and 3 microg/mL. Compounds 1-4 possessed cytotoxicity toward insect cells (fall armyworm and mosquito larvae, IC(50) of 11-72 microg/mL). Furanoid diterpenes 3 and 4 also exhibited cytotoxicity against the Vero cell line with respective IC(50)'s of 31 and 28 microg/mL, while 1 and 2 were inactive at 50 microg/mL. Compounds 1-4 were inactive (at 20 microg/mL) against KB and BC cell lines and showed only weak antimycobacterial activity against Mycobacterium tuberculosis H37Ra with minimum inhibitory concentrations of 50-100 microg/mL.

Structures of eleven bioxanthracenes (1 approximately 11) and two monomers (12 and 13), isolated from the insect pathogenic fungus Cordyceps pseudomilitaris BCC 1620, were elucidated. The structure, including the axial stereochemistry, of one of the major symmetrical dimers (1) was determined by X-ray crystallographic analysis, while the stereochemistries of the other isomers were deduced by chemical conversions and spectroscopic means.

Eleven bioxanthracenes and two monomers, six novel in nature, were isolated from the insect pathogenic fungus Cordyceps pseudomilitaris BCC 1620. Growth optimization of the strain led to the improvement of bioxanthracenes production. The bioxanthracenes were evaluated for their antimalarial activity and cytotoxicity.

Bioassay-guided fractionation of the crude extract from the insect pathogenic fungus Paecilomyces tenuipes BCC 1614 led to the isolation and identification of two antimycobacterial and antiplasmodial cyclodepsipeptides, beauvericin and beauvericin A.

The nature of the interactions between Plasmodium falciparum dihydrofolate reductase (pfDHFR) and antimalarial antifolates, i.e., pyrimethamine (Pyr), cycloguanil (Cyc) and WR99210 including some of their analogues, was investigated by molecular modeling in conjunction with the determination of the inhibition constants ( K i ). A three-dimensional structural model of pfDHFR was constructed using multiple sequence alignment and homology modeling procedures, followed by extensive molecular dynamics calculations. Mutations at amino acid residues 16 and 108 known to be associated with antifolate resistance were introduced into the structure, and the interactions of the inhibitors with the enzymes were assessed by docking and molecular dynamics for both wild-type and mutant DHFRs. The K i values of a number of analogues tested support the validity of the model. A ‘steric constraint’ hypothesis is proposed to explain the structural basis of the antifolate resistance.

The antimalarial activity of a number of artemisinin derivatives, both newly synthesized and currently used as drugs, against Plasmodium falciparum in culture shows a correlation with their affinity of binding with ferroprotoporphyrin IX, as measured from the spectral change of the latter. The new C-16-functionalized artemisinin derivatives were obtained through a novel one-pot synthesis of artemisitene (2) from naturally abundant artemisinin (1), followed by Michael addition with nucleophiles. The correlation points to the biological significance of the interaction of these derivatives with ferroprotoporphyrin IX and may provide a basis for primary screening of peroxidic antimalarials of similar structures.

Two new stilbene derivatives, lakoochins A (1) and B (2), were isolated from the roots of Artocarpus lakoocha. The structures of 1 and 2 were elucidated by analysis of their spectral data. Lakoochins A (1) and B (2) exhibited antimycobacterial activity with the respective MIC values of 12.5 and 50 microg/mL. While 1 was cytotoxic against the BC (breast cancer) cell line (IC(50) 6.1 microg/mL) but inactive (at 20 microg/mL) toward KB (nasopharyngeal carcinoma) cells, compound 2 possessed cytotoxicity against the BC and KB cell lines with IC(50) values of 3.1 and 6.1 microg/mL, respectively.