ChemInform Abstract: Synthesis of Some Biologically Active Heterocycles. Reactions of the Hydrazide of 2′-Thienoyl Anthranilic Acid and Its 3,5-Dibromo Derivative.

H. A. ABDEL-HAMID; S. A. SHIBA; A.-M. A. EL-KHAMRY; A. S. A. YOUSSEF

doi:10.1002/chin.199319086

SYNTHESIS OF SOME BIOLOGICALLY ACTIVE HETEROCYCLES. REACTIONS OF THE HYDRAZIDE OF 2′-THIENOYL ANTHRANILIC ACID AND ITS 3,5-DIBROMO DERIVATIVE

Phosphorus Sulfur and Silicon and the Related Elements ◽

10.1080/10426509208031557 ◽

1992 ◽

Vol 72 (1-4) ◽

pp. 237-247 ◽

Cited By ~ 6

Author(s):

Hoda A. Abdel-hamid ◽

Sayed A. Shiba ◽

Abdel-Momen A. El-khamry ◽

Ahmed S. A. Youssef

Keyword(s):

Anthranilic Acid ◽

Biologically Active ◽

Dibromo Derivative

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Quinazolin-4-One: A Varsatile Molecule

Current Bioactive Compounds ◽

10.2174/1573407215666181120115313 ◽

2020 ◽

Vol 16 (4) ◽

pp. 370-382

Author(s):

Rakesh D. Amrutkar ◽

Sunil V. Amrutkar ◽

Mahendrasing S. Ranawat

Keyword(s):

Anthranilic Acid ◽

Molecular Design ◽

Research Literature ◽

Biologically Active ◽

Research Papers ◽

Biological Importance ◽

New Chemical Entities ◽

Methods Of Synthesis ◽

Quinazoline Derivatives

Background:Quinazolines and quinazolinones constitute a major class of biologically active molecules both from natural and synthetic sources. We will limit this review to compounds possessing the 4(3H)-quinazolinone skeleton, which is found in compounds displaying significant biological and pharmacological properties. The molecular design of potential lead compound is still a key line of approach for the discovery and development of new chemical entities. A combination of two or more chemical moieties into one is a common approach of operation and this can most likely result in the improvement of pharmacological activity and removal of unwanted side effects.Methods:We undertake search for peer-reviewed and research literature on quinazolinone moiety using different tools of literature survey. The quality of superior papers was assess using standard tools. The distinctiveness of screened papers was shorted and high-quality content was reorganiz and written in own language.Results:The review will be expressed in two main sections, the first section will be related to synthetic procedures and the second section includes the biological importance of Quinazoline derivatives. Total hundred (100) to one hundred and ten (110) research papers ware searched. Out of these, seventy-eight papers were included in the review, the majority of research papers were from international journals. Fifty fours papers defined the different synthetic schemes considering the general strategies using orthosubstituted anilines such as 2-aminobenzoic acid (anthranilic acid) and its analogues, or isatoic anhydride as starting materials, which are condensed with acid chlorides, imidates or aldehydes. Microwave irradiation was also proven to be very useful to improve the yields, and in particular, it has been successfully applied to the Niementowski procedure involving the fusion of anthranilic acid with formamide. The remaining part of the review focuses on biological importance of the 4(3H)-quinazolinone scaffold as therapeutic agents and a broad range of activities like antibacterial, antifungal, antiviral, anticonvulsant, antitumor, antihypertensive, analgesic and anti-inflammatory agents has been highlighted.Conclusion:The present review focuses on simplified, efficient and widespread literature of the methods of synthesis and diverse pharmacological activities of quinazoline and its derivatives have been highlighted.

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Characterization of photosystem II with the atomic-force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130365 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1146-1147

Author(s):

Kathleen M. Marr ◽

Mary K. Lyon

Keyword(s):

Photosystem Ii ◽

Atomic Force Microscope ◽

Three Dimensional ◽

Biologically Active ◽

Atomic Force ◽

Freeze Etching ◽

Image Averaging ◽

Oxygen Evolving ◽

Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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Depletion and Reconstitution of Active E. Coli Ribosomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116826 ◽

1975 ◽

Vol 33 ◽

pp. 640-641

Author(s):

M. Boublik ◽

W. Hellmann ◽

F. Jenkins

Keyword(s):

Protein Biosynthesis ◽

Large Subunit ◽

High Resolution Electron Microscopy ◽

Small Subunit ◽

Structure And Function ◽

Biologically Active ◽

Biological Macromolecules ◽

E Coli ◽

Resolution Electron ◽

And Function

Correlations between structure and function of biological macromolecules have been studied intensively for many years, mostly by indirect methods. High resolution electron microscopy is a unique tool which can provide such information directly by comparing the conformation of biopolymers in their biologically active and inactive state. We have correlated the structure and function of ribosomes, ribonucleoprotein particles which are the site of protein biosynthesis. 70S E. coli ribosomes, used in this experiment, are composed of two subunits - large (50S) and small (30S). The large subunit consists of 34 proteins and two different ribonucleic acid molecules. The small subunit contains 21 proteins and one RNA molecule. All proteins (with the exception of L7 and L12) are present in one copy per ribosome.This study deals with the changes in the fine structure of E. coli ribosomes depleted of proteins L7 and L12. These proteins are unique in many aspects.

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Fractionation of the Biologically Active Large Molecular Components of Human Gastric Content

Gastroenterology ◽

10.1016/s0016-5085(19)35388-0 ◽

1959 ◽

Vol 37 (4) ◽

pp. 439-444 ◽

Cited By ~ 1

Author(s):

Ranwel Caputto ◽

William O. Smith ◽

Jordan Tang ◽

Raul E. Trucco ◽

Walter Joel ◽

...

Keyword(s):

Gastric Content ◽

Biologically Active ◽

Molecular Components

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Bioavailability of naringenin chalcone in humans after ingestion of cherry tomatoes

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000574 ◽

2020 ◽

Vol 90 (5-6) ◽

pp. 411-416 ◽

Cited By ~ 2

Author(s):

Carina Kolot ◽

Ana Rodriguez-Mateos ◽

Rodrigo Feliciano ◽

Katharina Bottermann ◽

Wilhelm Stahl

Keyword(s):

Plasma Levels ◽

Average Concentration ◽

Biologically Active ◽

Thiol Groups ◽

Structural Element ◽

Active Molecule ◽

Reactive Center ◽

Average Maximum ◽

Alpha Beta ◽

Cherry Tomatoes

Abstract. Chalcones are a type of flavonoids characterized by an α-β unsaturated structural element which may react with thiol groups to activate pathways such as the Nrf2-Keap-1 system. Naringenin chalcone is abundant in the diet but little is known about its bioavailability. In this work, the bioavailability of naringenin chalcone from tomatoes was investigated in a group of healthy men (n=10). After ingestion of 600 grams of tomatoes providing a single dose of 17.3 mg naringenin chalcone, 0.2 mg of naringenin, and 195 mg naringin plasma levels of free and conjugated naringenin and naringenin chalcone (glucuronide and sulfate) were analyzed by UHPLC-QTOF-MS at 0.5, 1, 3, and 6 h post-consumption. Plasma levels of conjugated naringenin increased to about 12 nmol/L with a maximum at about 3 h. Concentrations of free naringenin hardly elevated above baseline. Plasma levels of free and conjugated naringenin chalcone significantly increased. A maximum of the conjugated chalcone was reached at about 3 h after ingestion with an average concentration of about 0.5 nmol/L. No free chalcone was detectable at baseline but low amounts of the unconjugated compound could be detected with an average maximum of 0.8 nmol/L at about 1 h after ingestion. The data demonstrate that naringenin chalcone is bioavailable in humans from cherry tomatoes as a dietary source. However, availability is poor and intramolecular cyclisation as well as extended metabolism likely contribute to the inactivation of the reactive alpha-beta unsaturated reactive center as well as the excretion of the biologically active molecule, respectively.

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