Phenolic glycosides, a new class of human recombinant nucleotide pyrophosphatase phosphodiesterase-1 inhibitors

A comprehensive analysis on Symplocos racemosa Roxb.: Traditional uses, botany, phytochemistry and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Symplocos racemosa Roxb. belongs to a unigeneric family Symplocaceae, known as lodhra in Sanskrit; is a small evergreen tree, found throughout the tropical and sub-tropical countries. Ethnobotanical literature indicates use of S. racemosa in treatment of eye disease, skin diseases, ear diseases, liver and bowel complaints, tumors, uterine disorders, spongy and bleeding gums, asthma, fever, snake-bite, gonorrhea and arthritis. The main aim of this review is to provide detailed phytopharmacological profile on S. racemosa in support with the traditional practices and ethnomedicinal uses.

MATERIALS AND METHODS

All relevant worldwide accepted databases have been searched for the name "S. racemosa" along with other literature from Indian Classical texts and Pharmacopoeias. The accessible literatures available on S. racemosa, were collected through electronic search on Pub med, Scopus, Science direct and traditional reports.

RESULTS

S. racemosa is important Indian traditional drug used in many Ayurvedic and herbal formulations for treatment of liver as well as uterine disorders and leucorrhea. Majority of phytopharmacological reports are on stem bark of the plant which include anti-cancer, hepatoprotective, anti-oxidant, anti-androgenic effect, anti-inflammatory, wound healing activity and anti-diabetic effects. Phytochemical studies indicated presence of many phenolic glycosides like symplocoside, triterpenoids like betulinic acid, acetyloleanolic acid and oleanolic acid and flavonoids like quercetin which might have contributed to the observed protective effects.

CONCLUSION

Many ethnobotanical claims have been confirmed through systematic in-vitro and in-vivo pharmacological studies on different extracts of stem bark and isolated constituents. However, systematic studies on the bio-markers are desirable to establish mode of action and to validate the traditional claim in clinical practice after proper safety assessment. The conservation data of genus Symplocos showed risk of extinction due to restricted distribution in the wild hence systematic techniques should be developed for the maintenance of this plant.

Synthesis of triazole Schiff bases: novel inhibitors of nucleotide pyrophosphatase/phosphodiesterase-1

A series of Schiff base triazoles 1–25 was synthesized and evaluated for their nucleotide pyrophosphatase/phosphodiesterase-1 inhibitory activities. Among twenty-five compounds, three compounds 10 (IC50 = 132.20 ± 2.89 lM), 13 (IC50 = 152.83 ± 2.39 lM), and 22 (IC50 = 251.0 ± 6.64 lM) were identified as potent inhibitors with superior activities than the standard EDTA (IC50 = 277.69 ± 2.52 lM). The newly identified inhibitors may open a new avenue for the development of treatment of phosphodiesterase-I related disorders. These compounds were also evaluated for carbonic anhydrase, acetylcholinesterase and butyrylcholinesterase inhibitory potential and were found to be inactive. The compounds showed non-toxic effect towards PC3 cell lines.

Forest biorefinery: Potential of poplar phytochemicals as value-added co-products

The global forestry industry after experiencing a market downturn during the past decade has now aimed its vision towards the integrated biorefinery. New business models and strategies are constantly being explored to re-invent the global wood and pulp/paper industry through sustainable resource exploitation. The goal is to produce diversified, innovative and revenue generating product lines using on-site bioresources (wood and tree residues). The most popular product lines are generally produced from wood fibers (biofuels, pulp/paper, biomaterials, and bio/chemicals). However, the bark and other tree residues like foliage that constitute forest wastes, still remain largely an underexploited resource from which extractives and phytochemicals can be harnessed as by-products (biopharmaceuticals, food additives and nutraceuticals, biopesticides, cosmetics). Commercially, Populus (poplar) tree species including hybrid varieties are cultivated as a fast growing bioenergy crop, but can also be utilized to produce bio-based chemicals. This review identifies and underlines the potential of natural products (phytochemicals) from Populus species that could lead to new business ventures in biorefineries and contribute to the bioeconomy. In brief, this review highlights the importance of by-products/co-products in forest industries, methods that can be employed to extract and purify poplar phytochemicals, the potential pharmaceutical and other uses of >160 phytochemicals identified from poplar species - their chemical structures, properties and bioactivities, the challenges and limitations of utilizing poplar phytochemicals, and potential commercial opportunities. Finally, the overall discussion and conclusion are made considering the recent biotechnological advances in phytochemical research to indicate the areas for future commercial applications from poplar tree species.

Synthesis, characterization and biological evaluation of N-(2,3-dimethyl-5-oxo-1-phenyl-2,5-dihydro-1H-pyrazol-4-yl)benzamides

Comparison of active site residues of modelled h-GCAP with template h-PLAP.

Therapeutic potentials of ecto-nucleoside triphosphate diphosphohydrolase, ecto-nucleotide pyrophosphatase/phosphodiesterase, ecto-5'-nucleotidase, and alkaline phosphatase inhibitors

The modulatory role of extracellular nucleotides and adenosine in relevance to purinergic cell signaling mechanisms has long been known and is an object of much research worldwide. These extracellular nucleotides are released by a variety of cell types either innately or as a response to patho-physiological stress or injury. A variety of surface-located ecto-nucleotidases (of four major types; nucleoside triphosphate diphosphohydrolases or NTPDases, nucleotide pyrophosphatase/phosphodiesterases or NPPs, alkaline phosphatases APs or ALPs, and ecto-5'-nucleotidase or e5NT) are responsible for meticulously controlling the availability of these important signaling molecules (at their respective receptors) in extracellular environment and are therefore crucial for maintaining the integrity of normal cell functioning. Overexpression of many of these ubiquitous ecto-enzymes has been implicated in a variety of disorders including cell adhesion, activation, proliferation, apoptosis, and degenerative neurological and immunological responses. Selective inhibition of these ecto-enzymes is an area that is currently being explored with great interest and hopes remain high that development of selective ecto-nucleotidase inhibitors will prove to have many beneficial therapeutic implications. The aim of this review is to emphasize and focus on recent developments made in the field of inhibitors of ecto-nucleotidases and to highlight their structure activity relationships wherever possible. Most recent and significant advances in field of NTPDase, NPP, AP, and e5NT inhibitors is being discussed in detail in anticipation of providing prolific leads and relevant background for research groups interested in synthesis of selective ecto-nucleotidase inhibitors.

Chemical constituents and biological applications of the genus Symplocos

The genus Symplocos has been reviewed for its chemical constituents and biological activities including traditional importance of some common species. The plants of this genus contain terpenoids, flavonoids, lignans, phenols, steroids, alkaloids, and iridoids. Terpenoids are the major constituents within the genus Symplocos and most of them exhibit antiproliferative effects. Some phenolic glycoside derivatives showed inhibitory activity against snake-venom phosphodiesterase I and human nucleotide pyrophosphatase phosphodiesterase I. The members of genus Symplocos are well known for their traditional uses in the treatment of various diseases like leprosy, gynecological disorders, ulcers, leucorrhea, menorrhagia, malaria, and tumefaction. The aim of the present paper is to review the comprehensive knowledge of the plants of this genus including the traditional uses, chemistry, and pharmacology.

Neolignan glycosides from Symplocos caudata

A phytochemical investigation of the roots of Symplocos caudata Wall (Symplocaceae) resulted in isolation and characterization of four optical isomers of a neolignan glycoside (1-4), a lignan lactone glycoside (5), a phenylpropanoid glycoside (6), as well as two known compounds (7, 8). Their structures were elucidated as (7S,8S)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-beta-d-glucopyranoside (1), (7R,8R)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-beta-d-glucopyranoside (2), (7R,8S)-erythro-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-beta-d-glucopyranoside (3), (7S,8R)-erythro-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-beta-d-glucopyranoside (4), 8R,8'R-matairesinol-4-O-beta-d-xylopyranosyl-(1-->2)-O-beta-d-glucopyranoside (5), 1-O-[beta-d-xylopyranosyl-(1-->6)-O-beta-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), matairesinoside (7), and (R)-1-O-(beta-d-glucopyranosyl)-2-[2-methoxy-4-(omega-hydroxypropyl)-phenoxyl]-propan-3-ol (8) on the basis of spectroscopic data (1D and 2D NMR, MS and CD) and chemical evidence.

Chemical Constituents of Plants from the GenusSymplocos

The chemical constituents of Symplocos genus were reviewed with 90 structures and 28 references cited. These constituents include triterpenoids, flavonoids, lignans, phenols, steroids, alkaloids, and iridoids. Triterpenoids are the dominant constituents within the genus Symplocos, some of them exhibited antiproliferative effects. Some phenolic glycoside derivatives showed inhibitory activity against snake-venom phosphodiesterase I and human nucleotide pyrophosphatase phosphodiesterase.