Hypepontine, a new quaternary alkaloid with antimicrobial properties.

New isoquinoline alkaloid hypepontine (1) together with a five known compounds, were identified in Hypecoum ponticum Velen, the partial synonym of Hypecoum procumbens L. The structure of the new substance was elucidated based on spectroscopic evidence. The tertiary and quaternary alkaloid mixtures as well as the isolated alkaloids were evaluated for their antibacterial and antifungal activity. The result revealed that the crude alkaloid mixture containing quaternary isoquinoline alkaloids showed potent antifungal and antibacterial activity.

Alkaloids from the aerial parts of Leptopyrum fumarioides express immunomodulatory activity.

A new type aporphine-benzylisoquinoline alkaloid leptofumarine (1) was isolated from Leptopyrum fumarioides L. The structure of 1 was elucidated based on spectroscopic evidence. Leptofumarine together with the previously isolated leptopyrine (2) were evaluated for their effect on macrophages and bone marrow (BM) cells in vitro. Both alkaloids inhibited cytokine production by LPS-stimulated peritoneal macrophages. Leptopyrine suppressed osteoclast and osteoblast formation, while leptofumarine affected only osteoblastogenesis.

Evaluation of Glaucine Content in Bulgarian Black Sea Coast Localities of Glauciumflavum Cranz. (Papaveraceae).

The content of the alkaloid glaucine was evaluated in Glaucium flavum plants from seven localities along the Bulgarian Black sea coast during two consecutive years, in order to select those with highest glaucine content. Some fluctuations of glaucine content were observed during the two years, and in most of the localities the alkaloid was lower in 2015. Pomorie and Ahtopol maintained high percentages of glaucine in the dry plant material in the two investigated years, being 2.3% for Pomorie in 2014 and for Ahtopol in 2015. The lowest percentages of glaucine were recorded in the plant material from Shkorpilovtsi (0.9% and 0.6%, respectively in 2014 and 2015). Fluctuations in glaucine content were probably due to some abiotic factors as light, temperature, precipitation, soil substrate, salinity, etc.

Alkaloids of Seeds, in vitro Cultivated, and ex vitro Adapted Plants of the Bulgarian Endemic Species Papaver degenii (Papaveraceae).

Papaver degenii (Urum. & Jav.) Kuzmanov is a Bulgarian endemic and glacial relict growing in the alpine zone of Pirin Mountains and it is included in the Red Data Book of Bulgaria. Numerous plants were in vitro multiplied in order to study the alkaloid composition of the species and to test the potential for green biotechnology establishment. Percentages of the crude alkaloid mixture in dried in vitro shoots and ex vitro adapted plants to room phytoiron were similar to that in seeds (0.49%) and 5 to 6 times higher than in the aerial parts of wild-growing plants. Amurensine was the only alkaloid detected in the seeds. Four isoquinoline alkaloids were isolated from the regenerated plants, belonging to two alkaloid types: isopavines (amurensine and Ο-methylthalisopavine) and protopines (allocryptopine and protopine), amurensine being the main alkaloid: 63.4% in in vitro shoots, up to 88.1% in the aerial parts of ex vitro adapted plants. Allocryptopine was in higher amount (30%) in the roots of the ex vitro adapted plants.

Comparative Study of Alkaloid Pattern of Four Bulgarian Fumaria species.

The alkaloid pattern of four Fumaria species (Fumaria kralikii, Fumaria rostellata, Fumaria schleicherii, Fumaria thureii) growing in Bulgaria was investigated by GC-MS and twenty isoquinoline alkaloids were determined. Phytochemical investigation of the alkaloid composition on Fumaria thuretii Boiss was made for the first time. The alkaloid profile of the species was compared at two levels, between different species and within two species from different habitats. Two chemotypical groups, based on the types of isoquinoline alkaloids were suggested. To group A belong species F. kralikii, F. rostellata (F. r. 1) and F. thuretii containing more than 50% spirobenzylisoquinoline alkaloids of the crude alkaloid mixtures. To group B belong species F. rostellata (F. r. 2) and F. schleicherii containing more than 40% protopine alkaloids and relatively high percentage phthaldeisoquinoline alkaloids (11-19%). In group A phthaldeisoquinoline alkaloids were not detected.

Phosphatidylinositol 4-kinase III beta is the target of oxoglaucine and pachypodol (Ro 09-0179) for their anti-poliovirus activities, and is located at upstream of the target step of brefeldin A.

In recent years, phosphatidylinositol 4-kinase III beta (PI4KB) has emerged as a conserved target of anti-picornavirus compounds. In the present study, PI4KB was identified as the direct target of the plant-derived anti-picornavirus compounds, oxoglaucine and pachypodol (also known as Ro 09-0179). PI4KB was also identified as the target via which pachypodol interferes with brefeldin A (BFA)-induced Golgi disassembly in non-infected cells. Oxysterol-binding protein (OSBP) inhibitor also has interfering activity against BFA. It seems that this interference is not essential for the anti-poliovirus (PV) activities of BFA and PI4KB/OSBP inhibitors. BFA inhibited early to late phase PV replication (0 to 6 hr postinfection) as well as PI4KB inhibitor, but with some delay compared to guanidine hydrochloride treatment. In contrast with PI4KB/OSBP inhibitors, BFA inhibited viral nascent RNA synthesis, suggesting that BFA targets some step of viral RNA synthesis located downstream of the PI4KB/OSBP pathway in PV replication. Our results suggest that PI4KB is a major target of anti-picornavirus compounds identified in vitro for their anti-picornavirus activities and for some uncharacterized biological phenomena caused by these compounds, and that BFA and PI4KB/OSBP inhibitors synergistically repress PV replication by targeting distinct steps in viral RNA replication.

Anti-enteroviral triple combination of viral replication inhibitors: activity against coxsackievirus B1 neuroinfection in mice.

BACKGROUND: Chemotherapy is an important tool for controlling enterovirus infections, but clinically effective anti-enterovirus drugs do not currently exist, mainly due to the development of drug resistance. We investigated the combination effects of enterovirus replication inhibitors in order to limit this process. In previous studies, we showed the efficacy of consecutive alternating administration of the triple combinations disoxaril/guanidine/oxoglaucine and pleconaril/guanidine/oxoglaucine against coxsackievirus B1 infection in newborn mice. Drug sensitivity tests of the viral brain isolates showed that these drug combinations prevented the development of drug resistance. METHODS: In the current study, we replaced guanidine-HCl with enteroviral RNA synthesis inhibitor MDL-860 to test the effect of a new triple combination-pleconaril/MDL-860/oxoglaucine-applied via consecutive alternating administration in newborn mice infected subcutaneously with 20 MLD50 of coxsackievirus B1. RESULTS: The pleconaril/MDL-860/oxoglaucine combination via consecutive alternating administration showed high activity at the 75 mg/kg MDL-860 dose: a protective effect of 50% and a pronounced suppression of brain virus titers. Moreover, along with prevention of drug resistance, a phenomenon of increased drug sensitivity was established. MDL-860 sensitivity in pleconaril/MDL-860/oxoglaucine increased 8.2 times vs. placebo (29 times vs. monotherapy) on day 7 and oxoglaucine sensitivity-4.9 times vs. placebo (by 6.8 times vs. monotherapy) on day 13. As concerns pleconaril, a demonstrable prevention of drug resistance was registered without increase of drug sensitivity. Daily, simultaneous administration of pleconaril/MDL-860/oxoglaucine showed no protective effects and led to a rapid development of drug resistance. CONCLUSIONS: These results add new support for using consecutive alternating administration treatment courses to achieve clinically effective chemotherapy of enterovirus infections.

Acetylated derivative of glaucine inhibits joint inflammation in collagenase-induced arthritis.

CONTEXT: Osteoarthritis (OA) has become by far the most common joint disorder. A number of studies using OA animal models have explored the effects of agents that can modulate bone metabolism. OBJECTIVE: In the present study, we investigated the effect of acetylated derivative of plant alkaloid glaucine (ADG) on experimental OA in mice. MATERIALS AND METHODS: Arthritis was induced by two intraarticular (i.a.) injections of collaganase. Histopathological changes were observed through hematoxylin and eosine (H&E), safranin O and toluidine blue staining. Differentiation of bone marrow (BM) cells was evaluated by tartarate-resistant acid phosphatase (TRAP) assay. The expression of phospho-Janus kinase 2 (pJAK2) and phospho signal transducer and activator of transcription3 (pSTAT3) expression in the joints was determined by immunohistochemistry. RESULTS: We established that ADG significantly decreased cell infiltration (2.32 ± 0.14 versus 1.62 ± 0.13), cartilage loss (2.42 ± 0.12 versus 1.12 ± 0.10) and bone erosion (1.76 ± 0.13 versus 1.04 ± 0.14) in arthritic mice. It appeared that the substance inhibited in a dose-dependent manner osteoclast differentiation in vitro. ADG suppressed the expression of pJAK2 in the joint and partially affected the expression of pSTAT3. CONCLUSION: Present results suggest that ADG is a suitable candidate for further development as an anti-arthritic agent.

Leptopyrine, new alkaloid from Leptopyrum fumarioides L. (Ranunculaceae).

A new type of isoquinoline alkaloid leptopyrine was isolated from the aerial parts of Leptopyrum fumarioides L. (Ranunculaceae) of Mongolian origin. The known alkaloids protopine and thalifoline were isolated for the first time from this the species. All structures were established by physical and spectral analyses.

Chemical and antiviral study on alkaloids from Papaver pseudocanescens M. Pop.

The phytochemical investigation of the aerial parts of Papaver pseudocanescens M. Pop. of Mongolian origin resulted in the isolation and structural elucidation of 8 alkaloids of the isoquinoline and promorphinane type. 8,14-Dihydroamurine, 8,14-dihydroflavinantine, and flavinantine are promorphinanes. Alborine, mecambridine, and mecambridine methohydroxide are retroprotoberberines. Amurensinine is an isopavine alkaloid and O-methylarmepavine is a benzylisoquinoline alkaloid. O-Methylarmepavine is a new alkaloid for the genus Papaver. Promorphinane-type alkaloids have been found for the first time in the species. All structures were established by physical and spectral analysis. As a first attempt to describe some of the biological activities of these alkaloids, the antiviral effect was tested against the in vitro replication of several viruses which belong to different taxonomic groups and represent significant human pathogens. Based on the results, the conclusion could be drawn that particular alkaloids from P. pseudocanescens possess selective antiviral effects against the replication of poliovirus 1 and human rhinovirus 14, two viruses from the Enterovirus genus of the Picornaviridae family.

Toll-like receptor-mediated anti-inflammatory action of glaucine and oxoglaucine.

Two isochinoline alkaloids, glaucine and oxoglaucine were investigated for their suggested anti-inflammatory influence concerning nitric oxide and cytokine production. Mouse peritoneal macrophages were stimulated with different Toll-like receptor (TLR) ligands such as LPS for TLR4, zymosan for TLR2 and CpG for TLR9. The alkaloids inhibited TNF-alpha and IL-6 production induced by these ligands. In regard to IL-12 suppressive effect was registered in the case of CpG stimulation. Glaucine succeeded to enhance LPS and zymosan-induced IL-10 production. The reduction of pro-inflammatory cytokines and increase of anti-inflammatory IL-10 are indicative for their use in different acute and chronic inflammatory diseases.

Alkaloids from Mongolian species Hypecoum lactiflorum Kar. et Kir. Pazij.

A new secoberbine alkaloid (-)-N-methylcorydalisol was isolated from the aerial parts of Hypecoum lactiflorum Kar. et Kir. Pazij. (Papaveraceae) of Mongolian origin and was characterised. The known alkaloids of protopine and protoberberine type protopine, allocryptopine, (-)-N-methylcanadine and (-)-N-methylstylopine were also isolated. (-)-N-methylstylopine is a new alkaloid for the genus, while (-)-N-methylcanadine is new for the species. All structures were established by physical and spectral analysis.

Cinnamoyl- and hydroxycinnamoyl amides of glaucine and their antioxidative and antiviral activities.

The aporphine alkaloid glaucine has been converted into 3-aminomethylglaucine and its free amino group has been linked to cinnamic, ferulic, sinapic, o-, and p-coumaric acids. The antioxidative potential of the synthesized amides was studied against DPPH(*) test. All of the tested compounds demonstrated higher radical scavenging activity than glaucine and 3-aminomethylglaucine, and lower antioxidative effect than the free hydroxycinnamic acids. The newly synthesized compounds were tested in vitro for antiviral activity against viruses belonging to different taxonomic groups.

Alkaloids from Papaver nudicaule L.

A new promorphinane alkaloid (-)-8,14-dihydroflavinantine was isolated from the aerial parts of Papaver nudicaule L. (Papaveraceae) growing in Mongolia. Six known isoquinoline alkaloids (+)-amuronine, pseudoprotopine, allocryptopine, (-)-dihydroamuronine, (-)-amurensinine N-oxide A and (-)-amurensinine N-oxide B were isolated, too. Pseudoprotopine has been found for the first time in a plant of the family Papaveraceae. (-)-dihydroamuronine, (-)-amurensinine N-oxide A and (-)-amurensinine N-oxide B are new for the genus Papaver. All structures were established using spectral and physical data.

A new 8,14-dihydropromorphinane alkaloid from Papaver nudicaule L.

A racem. 8,14-dihydroamurine is a new promorphinane alkaloid isolated from the aerial parts of Papaver nudicaule L. (Papaveraceae) of Mongolian origin. The known promorphinane and isopavine alkaloids (+)-amurine, (-)-amurensinine, (-)-O-methylthalisopavine, (-)-flavinantine and (-)-amurensine were also described. All structures were established by physical and spectral analysis. Flavinantine has been found for the first time in the species.

Alkaloids from Isopyrum thalictroides L.

Two new aporphine-benzylisoquinoline alkaloids thaliphine and isothaliphine with a new type of ether bridge were isolated from the roots and rhyzomes of Isopyrum thalictroides L. (Ranunculaceae). Their structures were established by physical and spectral analysis. The known alkaloid N-methylglaucine was isolated for the first time from a plant of the family Ranunculaceae.

Alkaloid spectrum in diploid and tetraploid hairy root cultures of Datura stramonium.

Hairy root cultures were obtained from diploid and induced tetraploid plants of Datura stramonium and analyzed by gas chromatography/mass spectrometry. Twenty alkaloids (19 for diploid and 9 for tetraploid hairy root cultures) were identified. A new tropane ester 3-tigloyloxy-6-propionyloxy-7-hydroxytropane was identified on the basis of mass spectral data. Hyoscyamine was the main alkaloid in both diploid and tetraploid cultures. In contrast to diploid hairy roots, the percentage contributions of the alkaloids, with exceptions for hyoscyamine and apoatropine, were higher in the total alkaloid mixture of tetraploid hairy roots.

GC-MS investigation of tropane alkaloids in Datura stramonium.

Alkaloids, GS-MS, Datura stramonium The alkaloid spectrum in roots, leaves and seeds of Datura stramonium L. was investigated by GC-MS. Twenty-nine tropane alkaloids are detected. Twelve of them are new constituents for the species and the two tropane esters 3-(3'-acetoxytropoyloxy)tropane (21) and 3-(2'-hydroxytropoyloxy)tropane (26) are described for the first time.