Search

Phytochemical investigation of the aerial parts of Perovskia abrotanoides (Lamiaceae) by normal phase column chromatography resulted in the isolation of perovskanol ( 1 ), a novel sesquiterpenoid possessing a 5/7/5 fused carbon ring skeleton. The structure of 1 was established by comprehensive spectroscopic data analysis including 1 D and 2 D NMR and HRESIMS. The antiprotozoal activity of compound 1 was evaluated against Trypanosoma brucei rhodesiense , T. cruzi , Leishmania donovani , Plasmodium falciparum and no promising activities were shown against all parasite tested.

Purpose: Zhumeria majdae, a unique species of the Zhumeria genus, is an endemic Iranian plant in the Lamiaceae family. Phytochemical investigation and biological activity of this plant are rarely reported. The current study aimed to find new antiprotozoal compounds from the roots of Z. majdae and to determine the absolute configuration of isolated compounds by circular dichroism., Methods: The extraction process from roots and aerial parts of Z. majdae was carried out by hexane, ethyl acetate and methanol followed by testing their antiprotozoal effects against Leishmania donovani, Trypanosoma brucei rhodesiense, T. cruzi, and Plasmodium falciparum, respectively. Structure elucidation was done using 1D and 2D NMR spectroscopy and HREIMS spectrometry. In addition, experimental and theoretical circular dichroism spectroscopy was used to establish absolute configuration., Results: In comparison with aerial parts, the hexane extract from roots showed superior activity against T. b. rhodesiense, L. donovani and P. falciparum with IC 50 values of 5.4, 1.6 and 2.1 μg/ml, respectively. From eight abietane-type diterpenoids identified in roots, six were reported for the first time in the genus Zhumeria. 11,14-dihydroxy-8,11,13-abietatrien-7-one (6) exhibited a promising biological activity against P. falciparum (IC 50 8.65 μM), with a selectivity index (SI) of 4.6, and lanugon Q (8) showed an IC 50 value of 0.13 μM and SI of 15.4 against T. b. rhodesiense., Conclusion: Altogether, according to the results, of 8 isolated compounds, dihydroxy-8,11,13-abietatrien-7-one (6) and lanugon Q (8) exhibited a promising activity against T. b. rhodesiense and P. falciparum. In conclusion, these compounds could be potential candidates for further analysis and may serve as lead compounds for the synthesis of antiprotozoal agents. Graphical abstract.

Novel isothiocyanate derivatives were synthesized starting from noscapine, bile acids, amino acids, and some aromatic compounds. Antiparasitic activities of the synthesized derivatives were tested against four unicellular protozoa, i.e., Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani, and Plasmodium falciparum. Interestingly, seven isothiocyanate analogues displayed promising antiparasitic activity against Leishmania donovani with IC 50 values between 0.4 and 1.0 µM and selectivity index (SI) ranged from 7.8 to 18.4, comparable to the standard drug miltefosine (IC 50  = 0.7 μM). Compound 7h demonstrated the best antileishmanial activity with an IC 50 value of 0.4 µM. Seven products exhibited inhibition activity against T. brucei rhodesiense with IC 50 s below 2.0 μM and SI between 2.7 and 29.3. Four primary amine derivatives of noscapine and five isothiocyanate derivatives exhibited antiplasmodial activity with IC 50 s in the range of 1.1-2.7 µM and SI values between 1.1 and 14.5. The isothiocyanate derivative 7c showed against T. cruzi with an IC 50 value of 1.9 µM and SI 4. Molecular docking and ADMET studies were performed to investigate the interaction between active ligands and T. brucei trypanothione reductase active site. The docking studies showed significant binding affinity of noscapine derivatives to enzyme active site and good compatibility with experimental data., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Novel N-substituted noscapine derivatives were synthesized by a three-component Strecker reaction of cyclic ether of N-nornoscapine with varied aldehydes, in the presence of cyanide ion. Moreover, the corresponding amides were synthesized by the oxidation of cyanide moieties in good yields. The in vitro antiprotozoal activity of the products was also investigated. Interestingly, some analogues did put on display promising antiparasitic activity against Trypanosoma brucei rhodesiense with IC 50 values between 2.5 and 10.0 µM and selectivity index (SI) ranged from 0.8 to 13.2. Eight compounds exhibited activity against Plasmodium falciparum K1 strain with IC 50 ranging 1.7-6.4 µM, and SI values between 2.8 and 10.5 against L6 rat myoblast cell lines. Molecular docking was carried out on trypanothione reductase (TbTR, PDB ID: 2WOW) and UDP-galactose 4' epimerase (TbUDPGE PDB: 1GY8) as targets for studying the envisaged mechanism of action. Compounds 6j 2 and 6b 2 displayed excellent docking scores with -8.59 and -8.86 kcal/mol for TbTR and TbUDPGE, respectively., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A phytochemical investigation of extracts from flowers and aerial parts of Tanacetum sonbolii afforded 7 new germacranolide sesquiterpene lactones. The structures were established by a combination of 1- and 2-dimensional nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and electronic circular dichroism. The in vitro antiprotozoal activity of the compounds against Trypanosoma brucei rhodesiense and cytotoxicity against rat myoblast (L6) cells were determined. Compounds 4: and 5: showed IC 50 values of 5.1 and 10.2 µM and selectivity indices of 3.9 and 4.0, respectively., Competing Interests: The authors declare no conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

Fractionation of the n-hexane extract of Salvia hydrangea afforded seven isoprenoids including six new compounds (1-6) and salvadione A (7). Their structures were established by comprehensive spectroscopic and spectrometric data analysis (1D and 2D NMR, HRMS). The absolute configuration of salvadione A (7) was established by single-crystal X-ray diffraction analysis with Cu/Kα radiation. In addition, the absolute configuration of all compounds was determined by electronic circular dichroism spectroscopy. A biosynthetic pathway for the formation of the scaffold of 1 is proposed. The antiprotozoal activity of the compounds against Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani, and Plasmodium falciparum was determined, and cytotoxicity was assessed in rat myoblast L6 cells. Perovskone C (2) exhibited good activity against P. falciparum (IC 50 0.6 μM) and a selectivity index of 62.2.

As part of a screening for new antiparasitic natural products from Iranian plants, n -hexane and ethyl acetate extracts from the aerial parts of Perovskia abrotanoides were found to exhibit strong inhibitory activity against Trypanosoma brucei rhodesiense and Leishmania donovani . The activity was tracked by high-performance liquid chromatography (HPLC)-based activity profiling. Preparative isolation by a combination of silica gel column chromatography and HPLC afforded 17 diterpenoids (1: -17: ), including 14 abietane-, two icetexane-, and one isopimarane-type derivatives. Among these, (5 R ,10 S )-11-hydroxy-12-methoxy-20-norabieta-8,11,13-triene (2: ), 12-hydroxy-norabieta-1(10),8,11,13-tetraene-1,11-furan (6: ), and 12-methoxybarbatusol (9: ) were new compounds, the structure of which was established by comprehensive spectroscopic data analysis (one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism). The antiprotozoal activity of the isolated compounds was evaluated against T. b. rhodesiense, Trypanosoma cruzi, L. donovani , and Plasmodium falciparum . Selectivity indexes (SI) were calculated in comparison to cytotoxicity on rat myoblast (L6) cells. Particularly active were 7 α -ethoxyrosmanol (4: ) with an IC 50 of 0.8 µM against T. b. rhodesiense (SI 14.9) and an IC 50 of 1.8 µM (SI 6.9) against L. donovani , ferruginol (8: ) with an IC 50 of 2.9 µM (SI 19.2) against P. falciparum , and miltiodiol (10: ) with an IC 50 of 0.5 µM (SI 10.5) against T. b. rhodesiense . None of the compounds exhibited selective toxicity against T. cruzi (SI ≤ 1.6)., Competing Interests: The authors declare no conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

Phytochemical investigation of the lipophilic extract of the roots of Salvia leriifolia resulted in the isolation of the new rearranged abietane diterpenoids leriifoliol (1) and leriifolione (2), together with 10 known diterpenoids. Structure elucidations were performed via extensive NMR and HRESIMS data, and the absolute configurations of compounds 1 and 3-5 were established by evaluation of experimental and calculated ECD spectra. The antiplasmodial activity of the new isolates was assayed against Trypanosoma brucei rhodesiense, T. cruzi, Plasmodium falciparum, and Leishmania donovani and also toxicity against rat myoblast (L6) cells. Compound 1 displayed antimalarial and low cytotoxic activity with IC 50 values of 0.4 and 33.6 μM, respectively, and a selectivity index of 84. Compound 2 displayed activity against T. brucei, T. cruzi, and L. donovani, with IC 50 values of 1.0, 4.6, and 1.0 μM, respectively. Putative biosynthetic pathways toward the formation of 1, 2, and 3 are proposed. Leriifoliol (1) is the first 20- nor-9,10- seco-abietane, while 2 exhibits an uncommon 6-6-5 fused-ring system.

Salvadione C (1) and perovskone B (2), two new triterpenoids with rare carbon skeletons, were isolated from an antiplasmodial n-hexane extract of Salvia hydrangea. The absolute configuration was determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. In vitro activity against Plasmodium falciparum K1 strain, Trypanosoma brucei rhodesiense STIB 900 strain, and cytotoxicity in rat myoblast (L6) cells were determined. Compounds 1 and 2 showed in vitro antiplasmodial activity, with IC50 values of 1.43 and 0.18 μM and selectivity indices (SI) of 86.2 and 69.6, respectively. IC50 values against T. brucei rhodesiense were found to be 4.33 and 15.92 μM, respectively.