Dehatrine, an antimalarial bisbenzylisoquinoline alkaloid from the Indonesian medicinal plant Beilschmiedia madang, isolated as a mixture of two rotational isomers

First Total Syntheses of Natural Phenanthrene Alkaloids, Uvariopsamine, Noruvariopsamine, 8-Hydroxystephenanthrine, 8-Methoxyuvariopsine, Thalihazine, and Secophoebine, and Their Potential as Antimalarial Agents

The first total syntheses of natural phenanthrene alkaloids, namely, uvariopsamine (1), noruvariopsamine (2), 8-hydroxystephenanthrine (3), 8-methoxyuvariopsine (4), thalihazine (5), and secophoebine (6), have been realized. In addition, their in vitro antimalarial activity against the multidrug-resistant K1 strain of Plasmodium falciparum and in vitro cytotoxic activity against the human nasopharynx carcinoma (KB), small cell lung cancer (NCI-H187), and breast cancer (MCF7) human cancer cell lines were investigated. All the phenanthrene alkaloids showed significant antiplasmodial activity (IC₅₀ 1.07-7.41 µM), and most compounds displayed low to no toxicity against the three cancer cell lines tested. Particularly, 3 exhibited the best antimalarial activity with an IC₅₀ value of 1.07 µM, no toxicity to NCI-H187 (IC₅₀ > 50 µM), and low toxicity against KB (IC₅₀ 24.53 µM) and MCF7 (IC₅₀ 42.67 µM) cell lines.

Alkaloids from the root of Indonesian Annona muricata L

Annona muricata L. has been used traditionally in Indonesia to treat disease. Phytochemical studies on the alkaloid fractions from the root of Annona muricata L. from Malang-Indonesia resulted in the isolation of an unreported benzylisoquinoline alkaloid (+)-xylopine 5 as well as four known alkaloids (1-4). The crude methanol extract and alkaloid fractions were tested against Plasmodium falciparum K1 and against bacteria (Escherichia coli, Klebsiella pneumonia, Acinetobacter buamanii, Pseudomonas aeruginosa, Methicillin-resistant Staphylococcus aureus) with insignificant activities (MIC > 32 µg/mL). Individual alkaloids were tested against a human suspension cancer cell line (HL-60 leukemia cells) and two human fibroblastic cancer cell lines (A549 lung cancer cells and HepG2 liver cancer cells) in which compound 5 was the most toxic alkaloid with IC₅₀ values ranging from 20 to 80 µM.

Chemical Composition and Anti-phytopathogenic Activity of the Essential Oil of Beilschmiedia miersii

Beilschmiedia miersii (Gay) Kosterm. (Lauraceae) (“Belloto del Norte”) is a little-studied tree endemic of the Central Zone of Chile. Hydrodistillation of leaves and stem bark of B. miersii yielded 0.2% essential oil. GC-MS analysis allowed identification of 31 components. The most abundant compounds were three phenylpropanoids: Sarisan (45.8%), eugenol methyl ether (27.7%) and safrole (5.8%). The oil of B. miersii showed high antioxidant content (TEAC: 750.8 ± 9.6 μmol/100 g of essential oil). The anti-phytopathogenic activity was evaluated against pathogens of plants: Fungi (Botrytis cinerea, Gibberella fujikuroi and Phytophthora cinnamomi) and bacteria: (Erwinia carotovora, Pseudomonas syringae and Agrobacterium tumefaciens). The oil showed anti-phytopathogenic activity against all tested bacteria and fungi, especially against A tumefaciens (IC50 = 5 μg / mL) and P. cinnamomi (IC50 = 200 μg / mL). This study demonstrates that the essential oil of B. miersii has great potential for applications in food and agricultural industries.

Endiandric Acid Derivatives and Other Constituents of Plants from the Genera Beilschmiedia and Endiandra (Lauraceae)

Plants of the Lauraceae family are widely used in traditional medicine and are sources of various classes of secondary metabolites. Two genera of this family, Beilschmiedia and Endiandra, have been the subject of numerous investigations over the past decades because of their application in traditional medicine. They are the only source of bioactive endiandric acid derivatives. Noteworthy is that their biosynthesis contains two consecutive non-enzymatic electrocyclic reactions. Several interesting biological activities for this specific class of secondary metabolites and other constituents of the two genera have been reported, including antimicrobial, enzymes inhibitory and cytotoxic properties. This review compiles information on the structures of the compounds described between January 1960 and March 2015, their biological activities and information on endiandric acid biosynthesis, with 104 references being cited.

Chemical compositions and biological activities of the essential oils of Beilschmiedia madang Blume (Lauraceae)

The present study aimed to examine the chemical compositions of the essential oils of Beilschmiedia madang and their antioxidant, antibacterial, antifungal, anticholinesterase and anti-tyrosinase activities. The major constituents of the essential oils of leaf and bark of B. madang were δ-cadinene (17.0 and 20.5 %), β-caryophyllene (10.3 and 6.7 %), α-cubebene (11.3 and 15.6 %), and α-cadinol (5.8 and 10.6 %). The essential oils were screened for their antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, β-carotene/linoleic acid bleaching, and total phenolic content. The bark oil showed the highest β-carotene/linoleic acid bleaching (90.3 % ± 0.2) and DPPH radical scavenging (IC50 212.0 µg/mL), while the highest phenolic content was exhibited by the leaf oil (94.5 % ± 0.3 mg GA/g). The antibacterial and antifungal activities were investigated by the disc diffusion and micro dilution method. The leaf and bark oils showed moderate activity towards Bacillus subtilis and Staphylococcus aureus with minimum inhibitory concentration (MIC) value 125 µg/mL. For antifungal assay, the bark oil showed strong activity towards Aspergillus niger and Aspergillus fumigatus with MIC value 62.5 µg/mL. Anticholinesterase and anti-tyrosinase activities were evaluated against Ellman method and mushroom tyrosinase, respectively. The results showed that leaf oil gave significant percentage inhibition (I%: acetylcholinesterase 55.2 %, butyrylcholinesterase 60.4 %, tyrosinase 53.1 %).

Secondary metabolites from the roots of Beilschmiedia tsangii and their anti-inflammatory activities

Four new endiandric acid analogues, tsangibeilin C (1), tsangibeilin D (2), tricyclotsangibeilin (3) and endiandric acid M (4), one new lignan, beilschminol B (5) and two new sesquiterpenes, (+)-5-hydroxybarbatenal (6) and (4R,5R)-4,5-dihydroxycaryophyll-8(13)-ene (7), together with four known compounds (8-11), were isolated from the roots of Beilschmiedia tsangii (Lauraceae). The structures of 1-7 were determined by spectroscopic techniques. Among the isolates, endiandric acid M (4) exhibited moderate iNOS inhibitory activity, with an IC(50) value of 31.70 μM.

Revealing Indigenous Indonesian Traditional Medicine: Anti-infective Agents

Indonesia is rich in medicinal plants which the population has used traditionally from generation to generation for curing diseases. Our interest in the treatment of infectious diseases has lead to the investigation of traditional Indonesian treatments. In this review, we present a comprehensive review of ethnopharmacologically directed screening in Indonesian medicinal plants to search for new antiviral, antimalarial, antibacterial and antifungal agents. Some potent drug leads have been isolated from Indonesian medicinal plants. Further research is still required for the lead development as well as the search for new bioactive compounds from the enormous medicinal plant resources.

Anti-inflammatory endiandric acid analogues from the roots of Beilschmiedia tsangii

Bioassay-guided fractionation of roots of Beilschmiedia tsangii led to the isolation of six new endiandric acid analogues: tsangibeilin A (1), tsangibeilin B (2), endiandramide A (3), endiandric acid K (4), endiandric acid L (5), and endiandramide B (6). Also isolated were two new lignans, beilschminol A (7) and tsangin C (8), and six known compounds. The structures of 1-8 were determined by spectroscopic techniques. Compounds 3 and 6 exhibited potent iNOS inhibitory activity, with IC(50) values of 9.59 and 16.40 μM, respectively.

(+)-Kunstlerone, a new antioxidant neolignan from the Leaves of Beilschmiedia kunstleri gamble

A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 µg/mL.

Annonaceae: bio-resource for tomorrow's drug discovery

One of the rich sources of lead compounds is the Angiosperms. Many of these lead compounds are useful medicines naturally, whereas others have been used as the basis for synthetic agents. These are potent and effective compounds, which have been obtained from plants, including anti-cancer (cytotoxic) agents, anti-malaria (anti-protozoal) agents, and anti-bacterial agents. Today, the number of plant families that have been extensively studied is relatively very few and the vast majorities have not been studied at all. The Annonaceae is the largest family in the order Magnoliales. It includes tropical trees, bushes, and climbers, which are often used as traditional remedies in Southeast Asia. Members of the Annonaceae have the particularity to elaborate a broad spectrum of natural products that have displayed anti-bacterial, anti-fungal, and anti-protozoal effects and have been used for the treatment of medical conditions, such as skin diseases, intestinal worms, inflammation of the eyes, HIV, and cancer. These special effects and the vast range of variation in potent compounds make the Annonaceae unique from other similar families in the Magnoliales and the Angiosperms in general. This paper attempts to summarize some important information and discusses a series of hypotheses about the effects of Annonaceae compounds.

(6,7-Dimethoxy-4-methylisoquinolinyl)-(4'-methoxyphenyl)-methanone, a new benzylisoquinoline alkaloid from Beilschmiedia brevipes

The leaves of Beilschmiedia brevipes provided a new benzylisoquinoline alkaloid: (6,7-dimethoxy-4-methylisoquinolinyl)-(4’-methoxyphenyl)-methanone (1) and O,O-dimethylannocherin A (2), a new natural compound which has been synthesized before. Complete ¹H- and ¹³C-NMR data of both compounds were reported. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and HRESIMS.

Bioactive constituents of the stem bark of Beilschmiedia zenkeri

Phytochemical investigation of the stem bark of Beilschmiedia zenkeri led to the isolation of four new methoxylated flavonoid derivatives, (2S,4R)-5,6,7-trimethoxyflavan-4-ol (1), (2S,4R)-4,5,6,7-tetramethoxyflavan (2), beilschmieflavonoid A (3), and beilschmieflavonoid B (4), together with seven known compounds. The structures of 1-4 were established by spectroscopic methods, and their relative configurations confirmed by X-ray crystallographic and CD analysis. The isolated compounds were evaluated in vitro for their antibacterial activity against three strains of bacteria, Pseudomonas agarici, Bacillus subtilis, and Streptococcus minor, and for their antiplasmodial activity against Plasmodium falciparum, chloroquine-resistant strain W2.

Isolation, structure elucidation and cytotoxic evaluation of endiandrin B from the Australian rainforest plant Endiandra anthropophagorum

Chemical investigations of the DCM extract from the roots of Endiandra anthropophagorum resulted in the isolation of a new cyclobutane lignan endiandrin B (1), together with the known natural products, endiandrin A (2), and (-)-dihydroguaiaretic acid (3). The structure of 1 was determined by extensive spectroscopic analyses, and confirmed by single crystal X-ray crystallography. Methylation of 1 using diazomethane afforded the previously reported natural product, cinbalansan (4). All compounds were evaluated for their cytotoxicity towards human lung carcinoma cells (A549) using high-content screening. (-)-Dihydroguaiaretic acid (3) was found to be the most potent cytotoxin against the A549 lung carcinoma cell line, with an IC(50) value of 7.49 microM.

Leaf Essential Oil Composition of Five Species of Beilschmiedia from Monteverde, Costa Rica

The leaf essential oils of five species of Beilschmiedia from Monteverde, Costa Rica (Beilschmiedia alloiophylla, B. brenesii, B. costaricensis, B. tilaranensis, and an undescribed Beilschmiedia species “chancho blanco”) have been obtained by hydrodistillation and analyzed by GC-MS in order to discern the differences and similarities between the volatile chemical compositions of these species. The principal constituents of B. alloiophylla leaf oil were germacrene D (18.9%), cis- and trans-β-ocimene (18.8% and 9.3%, respectively), α-pinene (11.8%), and bicyclogermacrene (9.1%). The leaf oil of B. brenesii was composed largely of the sesquiterpenes germacrene D (19.3%), β-caryophyllene (13.4%), α-copaene (9.0%), α-humulene (8.1%), and δ-cadinene (5.8%), and the carbonyl compounds 2-undecanone (12.8%), trans-2-hexenal (8.8%), and 2-tridecanone (3.8%). α-Bisabolol (72.1%) dominated the leaf oil of B. costaricensis, while B. tilaranensis had germacrene D (54.9%), β-caryophyllene (14.8%), and δ-cadinene (5.1%) as major components. Beilschmiedia “chancho blanco” leaf oil was composed largely of β-caryophyllene (16.6%), bicyclogermacrene (14.1%), and α-pinene (12.1%).

A search for natural bioactive compounds in Bolivia through a multidisciplinary approach. Part V. Evaluation of the antimalarial activity of plants used by the Tacana Indians

One hundred and twenty-five extracts of 122 different plant species traditionally used by the Tacana, a native community living in lowland forest at the base of the last foothills of the Cordillera Oriental of the Bolivian Andes, were screened for antimalarial activity in vitro on Plasmodium falciparum chloroquine resistant (D2) and sensitive strains (F32), and were evaluated in vivo on rodent malaria Plasmodium berghei. Five ethanolic stembark extracts showed marked activity either in vitro or in vivo, and only one of them, Bowdichia virgilioides being traditionally used against malaria, was active in vitro (IC50=1 microg/ml on both strains) and in vivo (51% at 100 mg/kg). Other active extracts were from Caesalpinia pluviosa bark displaying activity in vitro against chloroquine resistant strain (IC50 8.3 microg/ml), traditionally used against dysentery; two Lauraceae bark extracts, Nectandra aff. hihua and Licaria canella respectively used for construction purposes and against stomach ache, both displaying activity in vitro against P. falciparum sensible and resistant strains (IC50 around 4 microg/ml); finally, the bark of a strongly aromatic Burseraceae, Protium glabrescens exuding an anti-inflammatory and analgesic resin, was active in vivo only (61% at 100 mg/kg). Results are discussed in relation with Tacana traditional medicine.

Indonesian medicinal plants. VII. Seven new clerodane-type diterpenoids, peronemins A2, A3, B1, B2, B3, C1, and D1, from the leaves of Peronema canescens (Verbenaceae)

Seven new clerodane-type diterpenoids, named peronemins B2 (1), A2 (2), B1 (3), C1 (4), B3 (5), A3 (6), and D1 (7), were isolated from the leaves of Peronema canescens (Verbenaceae), an Indonesian medicinal plant collected in Bengkulu, Sumatera Island, Indonesia. The chemical structures of 1-7 have been elucidated on the basis of their chemical and physicochemical properties.