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The Alkaloids. Chemistry and Biology 2021This chapter provides a short overview of the history of morphine since it's isolation by Sertürner in 1805. The biosynthesis of the title alkaloid as well as all total... (Review)
Review
This chapter provides a short overview of the history of morphine since it's isolation by Sertürner in 1805. The biosynthesis of the title alkaloid as well as all total and formal syntheses of morphine and codeine published after 1996 are discussed in detail. The last section of this chapter provides a detailed overview of medicinally relevant derivatives of the title alkaloid.
Topics: Alkaloids; Biology; Codeine; Morphine
PubMed: 34565506
DOI: 10.1016/bs.alkal.2021.04.001 -
Molecules (Basel, Switzerland) Jun 2021Phytochemicals belonging to the group of alkaloids are signature specialized metabolites endowed with countless biological activities. Plants are armored with these... (Review)
Review
Phytochemicals belonging to the group of alkaloids are signature specialized metabolites endowed with countless biological activities. Plants are armored with these naturally produced nitrogenous compounds to combat numerous challenging environmental stress conditions. Traditional and modern healthcare systems have harnessed the potential of these organic compounds for the treatment of many ailments. Various chemical entities (functional groups) attached to the central moiety are responsible for their diverse range of biological properties. The development of the characterization of these plant metabolites and the enzymes involved in their biosynthesis is of an utmost priority to deliver enhanced advantages in terms of biological properties and productivity. Further, the incorporation of whole/partial metabolic pathways in the heterologous system and/or the overexpression of biosynthetic steps in homologous systems have both become alternative and lucrative methods over chemical synthesis in recent times. Moreover, in-depth research on alkaloid biosynthetic pathways has revealed numerous chemical modifications that occur during alkaloidal conversions. These chemical reactions involve glycosylation, acylation, reduction, oxidation, and methylation steps, and they are usually responsible for conferring the biological activities possessed by alkaloids. In this review, we aim to discuss the alkaloidal group of plant specialized metabolites and their brief classification covering major categories. We also emphasize the diversity in the basic structures of plant alkaloids arising through enzymatically catalyzed structural modifications in certain plant species, as well as their emerging diverse biological activities. The role of alkaloids in plant defense and their mechanisms of action are also briefly discussed. Moreover, the commercial utilization of plant alkaloids in the marketplace displaying various applications has been enumerated.
Topics: Acylation; Alkaloids; Biosynthetic Pathways; Glycosylation; Methylation; Molecular Structure; Oxidation-Reduction; Phytochemicals; Plant Physiological Phenomena; Plants
PubMed: 34204857
DOI: 10.3390/molecules26113374 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Oct 2020Pictet-Spenglerases (P-Sases) catalyze the Pictet-Spengler (P-S) reactions and exhibit high stereoselectivity and regioselectivity under mild conditions. The typical P-S... (Review)
Review
Pictet-Spenglerases (P-Sases) catalyze the Pictet-Spengler (P-S) reactions and exhibit high stereoselectivity and regioselectivity under mild conditions. The typical P-S reaction refers to the condensation and recyclization of β-arylethylamine with aldehyde or ketone under acidic conditions to form tetrahydroisoquinoline and β-carboline alkaloid derivatives. The related enzymatic products of P-Sases are the backbones of various bioactive compounds, including clinical drugs: morphine, noscapine, quinine, berberine, ajmaline, morphine. Furthermore, the activity of P-Sases in stereoselective and regioselective catalysis is also valuable for chemoenzymatic synthesis. Therefore, this review summarizes the research progress in the discovery, functional identification, biological characteristics and catalytic applications of P-Sases, which provide the useful theoretical reference in future P-Sases research and development.
Topics: Alkaloids; Catalysis; Enzymes; Research; Tetrahydroisoquinolines
PubMed: 33169566
DOI: 10.13345/j.cjb.200064 -
Natural Product Reports Sep 2021Covering: 1917 to 2020Tropane alkaloids (TAs) are a remarkable class of plant secondary metabolites, which are characterized by an 8-azabicyclo[3.2.1]octane (nortropane)... (Review)
Review
Covering: 1917 to 2020Tropane alkaloids (TAs) are a remarkable class of plant secondary metabolites, which are characterized by an 8-azabicyclo[3.2.1]octane (nortropane) ring. Members of this class, such as hyoscyamine, scopolamine, and cocaine, are well known for their long history as poisons, hallucinogens, and anaesthetic agents. Since the structure of the tropane ring system was first elucidated in 1901, organic chemists and biochemists have been interested in how these mysterious tropane alkaloids are assembled and . However, it was only in 2020 that the complete biosynthetic route of hyoscyamine and scopolamine was clarified, and their production in yeast was also achieved. The aim of this review is to present the innovative ideas and results in exploring the story of tropane alkaloid biosynthesis in plants from 1917 to 2020. This review also highlights that Robinson's classic synthesis of tropinone, which is one hundred years old, is biomimetic, and underscores the importance of total synthesis in the study of natural product biosynthesis.
Topics: Alkaloids; Biological Products; Molecular Structure; Tropanes
PubMed: 33533391
DOI: 10.1039/d0np00076k -
Molecules (Basel, Switzerland) Feb 2022The absolute stereochemistry of the marine alkaloid ()-()-tiruchanduramine was established via a convergent total synthesis in six steps and 15.5% overall yield from...
The absolute stereochemistry of the marine alkaloid ()-()-tiruchanduramine was established via a convergent total synthesis in six steps and 15.5% overall yield from Fmoc-D-Dab(Boc)-OH.
Topics: Alkaloids; Chemistry Techniques, Synthetic; Combinatorial Chemistry Techniques; Molecular Structure
PubMed: 35209136
DOI: 10.3390/molecules27041338 -
Current Opinion in Plant Biology Apr 2022Plants produce many compounds used by humans as medicines, including alkaloids of the benzylisoquinoline (BIA), monoterpene indole (MIA) and tropane classes. The... (Review)
Review
Plants produce many compounds used by humans as medicines, including alkaloids of the benzylisoquinoline (BIA), monoterpene indole (MIA) and tropane classes. The biosynthetic pathways of these pharmaceutical alkaloids are complex and spatially segregated across several tissues, cell-types and organelles. This review discusses the origin of primary metabolic inputs required by these specialized biosynthetic pathways and considers aspects relevant to their spatial organization. These factors are important for alkaloid production both in the native plants and for synthetic biology pathway reconstruction in microorganisms.
Topics: Alkaloids; Biosynthetic Pathways; Plants; Synthetic Biology
PubMed: 35219143
DOI: 10.1016/j.pbi.2022.102186 -
Molecules (Basel, Switzerland) Jan 2020The Pictet-Spengler reaction (P-S) is one of the most direct, efficient, and variable synthetic method for the construction of privileged pharmacophores such as... (Review)
Review
The Pictet-Spengler reaction (P-S) is one of the most direct, efficient, and variable synthetic method for the construction of privileged pharmacophores such as tetrahydro-isoquinolines (THIQs), tetrahydro-β-carbolines (THBCs), and polyheterocyclic frameworks. In the (five-year period) following its centenary birthday, the P-S reaction did not exit the stage but it came up again on limelight with new features. This review focuses on the interesting results achieved in this period (2011-2015), analyzing the versatility of this reaction. Classic P-S was reported in the total synthesis of complex alkaloids, in combination with chiral catalysts as well as for the generation of libraries of compounds in medicinal chemistry. The P-S has been used also in tandem reactions, with the sequences including ring closing metathesis, isomerization, Michael addition, and Gold- or Brønsted acid-catalyzed -acyliminium cyclization. Moreover, the combination of P-S reaction with Ugi multicomponent reaction has been exploited for the construction of highly complex polycyclic architectures in few steps and high yields. The P-S reaction has also been successfully employed in solid-phase synthesis, affording products with different structures, including peptidomimetics, synthetic heterocycles, and natural compounds. Finally, the enzymatic version of P-S has been reported for biosynthesis, biotransformations, and bioconjugations.
Topics: Alkaloids; Biological Products; Cyclization; Models, Molecular; Ruthenium
PubMed: 31963860
DOI: 10.3390/molecules25020414 -
Medicinal Chemistry (Shariqah (United... 2020Matrine-family alkaloids as tetracycloquinolizindine analogues from Traditional Chinese Medicine Sophora flavescens Ait, Sophora subprostrata and Sophora alopecuroides L... (Review)
Review
Matrine-family alkaloids as tetracycloquinolizindine analogues from Traditional Chinese Medicine Sophora flavescens Ait, Sophora subprostrata and Sophora alopecuroides L possess various pharmacological activities and have aroused great interests over the past decades. Especially, a lot of matrine derivatives have been designed and synthesized and their biological activities investigated, and encouraging results have continuously been achieved in recent several years. These studies are helpful to develop more potent candidates or therapeutic agents and disclose their molecular targets and mechanisms. This paper reviews recent advances in the bioactive modifications of matrine-family alkaloids from derivatization of the C-13, C-14 or C-15 position, opening D ring, fusing D ring and structural simplification.
Topics: Alkaloids; Drug Discovery; Humans; Quinolizines; Structure-Activity Relationship; Matrines
PubMed: 31378199
DOI: 10.2174/1573406415666190507121744 -
Journal of Experimental Zoology. Part... Jun 2022Sequestration of chemical defenses from dietary sources is dependent on the availability of compounds in the environment and the mechanism of sequestration. Previous...
Sequestration of chemical defenses from dietary sources is dependent on the availability of compounds in the environment and the mechanism of sequestration. Previous experiments have shown that sequestration efficiency varies among alkaloids in poison frogs, but little is known about the underlying mechanism. The aim of this study was to quantify the extent to which alkaloid sequestration and modification are dependent on alkaloid availability and/or sequestration mechanism. To do this, we administered different doses of histrionicotoxin (HTX) 235A and decahydroquinoline (DHQ) to captive-bred Adelphobates galactonotus and measured alkaloid quantity in muscle, kidney, liver, and feces. HTX 235A and DHQ were detected in all organs, whereas only DHQ was present in trace amounts in feces. For both liver and skin, the quantity of alkaloid accumulated increased at higher doses for both alkaloids. Accumulation efficiency in the skin increased at higher doses for HTX 235A but remained constant for DHQ. In contrast, the efficiency of HTX 235A accumulation in the liver was inversely related to dose and a similar, albeit statistically nonsignificant, pattern was observed for DHQ. We identified and quantified the N-methylation of DHQ in A. galactonotus, which represents a previously unknown example of alkaloid modification in poison frogs. Our study suggests that variation in alkaloid composition among individuals and species can result from differences in sequestration efficiency related to the type and amount of alkaloids available in the environment.
Topics: Alkaloids; Animals; Anura; Methylation; Poisons; Quinolines
PubMed: 35201668
DOI: 10.1002/jez.2587 -
Molecules (Basel, Switzerland) Mar 2023The pharmacological actions of benzylisoquinoline alkaloids are quite substantial, and have recently attracted much attention. One of the principle benzylisoquinoline... (Review)
Review
The pharmacological actions of benzylisoquinoline alkaloids are quite substantial, and have recently attracted much attention. One of the principle benzylisoquinoline alkaloids has been found in the unripe seed capsules of L. Although it lacks analgesic effects and is unrelated to the compounds in the morphine class, it is a peripheral vasodilator and has a direct effect on vessels. It is reported to inhibit the cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) phosphodiesterase in smooth muscles, and it has been observed to increase intracellular levels of cAMP and cGMP. It induces coronary, cerebral, and pulmonary artery dilatation and helps to lower cerebral vascular resistance and enhance cerebral blood flow. Current pharmacological research has revealed that papaverine demonstrates a variety of biological activities, including activity against erectile dysfunction, postoperative vasospasms, and pulmonary vasoconstriction, as well as antiviral, cardioprotective, anti-inflammatory, anticancer, neuroprotective, and gestational actions. It was recently demonstrated that papaverine has the potential to control SARS-CoV-2 by preventing its cytopathic effect. These experiments were carried out both in vitro and in vivo and require an extensive understanding of the mechanisms of action. With its multiple mechanisms, papaverine can be considered as a natural compound that is used to develop therapeutic drugs. To validate its applications, additional research is required into its precise therapeutic mechanisms as well as its acute and chronic toxicities. Therefore, the goal of this review is to discuss the major studies and reported clinical studies looking into the pharmacological effects of papaverine and the mechanisms of action underneath these effects. Additionally, it is recommended to conduct further research via significant pharmacodynamic and pharmacokinetic studies.
Topics: Humans; Papaverine; Opium; COVID-19; SARS-CoV-2; Alkaloids; Benzylisoquinolines
PubMed: 37049912
DOI: 10.3390/molecules28073149