Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Chemsitry of Natural Products-Flavonoids and quercetinSurendraKumar338
# Quercetin is the most abundant dietary flavonoid. It has been linked to improved exercise performance and reduced inflammation, blood pressure, and blood sugar level.
# Flavonoids any of large class of plant pigments having a structure based on or similar to that of flavone.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Chemsitry of Natural Products-Flavonoids and quercetinSurendraKumar338
# Quercetin is the most abundant dietary flavonoid. It has been linked to improved exercise performance and reduced inflammation, blood pressure, and blood sugar level.
# Flavonoids any of large class of plant pigments having a structure based on or similar to that of flavone.
Introduction, classification, isolation, purification, biological activity of alkaloids, general methods of structural determination of alkaloids, structural elucidation of Morphine, Reserpine and Emetine
Occurrence and classification of alkaloidsJasmineJuliet
Alkaloid definition, Alkaloid history, Occurrence of Alkaloids, Distribution of Alkaloids in nature, Classification of Alkaloids in Different categories, Pharmacological actions of Alkaloids. Alkaloids classification based on chemical structure, belongs to plant family, Based on Biochemical precursor, Based on Biological activity.
Extraction, isolation and structure elucidation of flavonoids: QuercetinMohammad Khalid
Extraction, isolation and structure elucidation of- Flavonoids Quercetin
Introduction
FLAVONOIDS & THEIR EXAMPLES
Quercetin
general isolation method
Extraction and isolation
Extraction from neem leaves
Isolation of Quercetin Methanolic Extract of Azadirachta indica leaves
Structure elucidation of Quercetin
Health benefits
Side Effects of Quercetin
Introduction to saponin glycosides, Saponin glycosides, Properties of saponin glycosides, Types of saponin glycosides, chemical tests of saponin glycosides
Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure are also termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.
Alkaloids are produced by a large variety of organisms including bacteria, fungi, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction. Alkaloids have a wide range of pharmacological activities including antimalarial (e.g. quinine), antiasthma (e.g. ephedrine), anticancer (e.g. homoharringtonine),cholinomimetic (e.g. galantamine), vasodilatory (e.g. vincamine), antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine),antibacterial (e.g. chelerythrine), and antihyperglycemic activities (e.g. piperine). Many have found use in traditional or modern medicine, or as starting points for drug discovery. Other alkaloids possess psychotropic (e.g. psilocin) and stimulant activities (e.g. cocaine, caffeine, nicotine, theobromine), and have been used in entheogenic rituals or as recreational drugs. Alkaloids can be toxic too (e.g. atropine, tubocurarine). Although alkaloids act on a diversity of metabolic systems in humans and other animals, they almost uniformly evoke a bitter taste
Introduction, classification, isolation, purification, biological activity of alkaloids, general methods of structural determination of alkaloids, structural elucidation of Morphine, Reserpine and Emetine
Occurrence and classification of alkaloidsJasmineJuliet
Alkaloid definition, Alkaloid history, Occurrence of Alkaloids, Distribution of Alkaloids in nature, Classification of Alkaloids in Different categories, Pharmacological actions of Alkaloids. Alkaloids classification based on chemical structure, belongs to plant family, Based on Biochemical precursor, Based on Biological activity.
Extraction, isolation and structure elucidation of flavonoids: QuercetinMohammad Khalid
Extraction, isolation and structure elucidation of- Flavonoids Quercetin
Introduction
FLAVONOIDS & THEIR EXAMPLES
Quercetin
general isolation method
Extraction and isolation
Extraction from neem leaves
Isolation of Quercetin Methanolic Extract of Azadirachta indica leaves
Structure elucidation of Quercetin
Health benefits
Side Effects of Quercetin
Introduction to saponin glycosides, Saponin glycosides, Properties of saponin glycosides, Types of saponin glycosides, chemical tests of saponin glycosides
Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure are also termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.
Alkaloids are produced by a large variety of organisms including bacteria, fungi, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction. Alkaloids have a wide range of pharmacological activities including antimalarial (e.g. quinine), antiasthma (e.g. ephedrine), anticancer (e.g. homoharringtonine),cholinomimetic (e.g. galantamine), vasodilatory (e.g. vincamine), antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine),antibacterial (e.g. chelerythrine), and antihyperglycemic activities (e.g. piperine). Many have found use in traditional or modern medicine, or as starting points for drug discovery. Other alkaloids possess psychotropic (e.g. psilocin) and stimulant activities (e.g. cocaine, caffeine, nicotine, theobromine), and have been used in entheogenic rituals or as recreational drugs. Alkaloids can be toxic too (e.g. atropine, tubocurarine). Although alkaloids act on a diversity of metabolic systems in humans and other animals, they almost uniformly evoke a bitter taste
This PPT include the description of flavonoids which is useful for pharmacognosy students. It include flavonoids description, classification and identification test.
Flavonoids, Definition, Classification, General Methods for the Structural determination of Flavonoids, Structural Elucidation of Quercetin, References.
FLAVONOIDSFLAVONOIDSClass of plant secondary metabolites
Word Flavonoids derived from the Latin word Flavus= yellow
Group of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable
Structure of flavonoids The flavonoids are possessing 15 carbon atoms and two benzene rings joined by a linear three-carbon chain the skeleton can be represented as the C6 - C3 - C6 system.
The three-carbon (-C3-) may be included through an oxygen bond between the two phenyl rings into
1- A five-membered heterocyclic ring (furan) as in aurones.
2- A six-membered heterocyclic ring (pyran) to give flavonoids which constitute the largest group. The flavonoid aglycone consists of a benzene ring (A) condensed with a six-membered ring (C) pyran ring, which at 2nd position adds a phenyl ring (B) as a substituent. C6-C3-C6 structure.
Crystalline solids sharp MP.
Solubility in H2O & alcohol (Flavonoid glycoside)
Non-glycosidic flavonoid: Aglycon part-sol in organic solvents
3. Color: Flavonones Flavanol Isoflavones- Colorless
Flavonols Flavones Yellow Chalchones aurones Orange
Anthocyanidine acid Red
In basic: Blue
4. Flavanols: optically active
15 C skeleton 2 benzene linked by heterocyclic pyran ring
Being phenolic dissolves in alkalies → Yellow sol +HCl → colorless
Glycosidic linkage located at 3 or 7 C
Flavanones, Flaonoes are unstable compounds on oxidation → Chalcones, leucocyanidines
Flavonoid + FeCl3→ green/ purple/ red-brown color
CLASSIFICATION OF FLAVONOIDSDepending on the carbon of the C ring on which the B ring is attached and the degree of unsaturation and oxidation of the C ring.
B ring is linked in position 3 of the ring C are called isoavones
B ring is linked in position 4, neoavonoids.
The B ring is linked in position 2 and further subdivided on the basis of the structural features of the C ring.
These subgroups are avones, avonols, avanones, avanonols, avanols or catechins and anthocyanins.
Finally avonoids with open C rings are called chalcones.
Flavones (2-phenylchromen-4-one)
Have a double bond between positions 2 and 3 and a ketone in position 4 of the C ring. ex:- Apigenin, Luteolin
2. Flavonols (3-hydroxy-2-phenylchromen-4-one)
Have a hydroxyl group in position 3 of the C ring, which may also be glycosylated. Ex: Kaempferol, Rutin, Myricetin, Quercetin.
. Flavanones/ dihydroavones (2,3-dihydro-2-phenylchromen-4- one
Have C ring saturated; the double bond between positions 2 and 3 is saturated, ex: Hesperetin, Hespereidin, Naringenin
Subclassified: furanoavanones, prenylated avanones, pyranoavanones or benzylated avanones
4. Flavanonols (dihydroavonols)/ 3-hydroxy-2,3-dihydro-2-phenyl chromen-4-one
Are 3-hydroxy derivatives of avanones; ex:Taxifolin, Silymarin
1. Shinoda test to dry powder or extract add 5 ml95% ethanol few drops of conc HCI and 0.5 g magnesium turnings Pink colour observed.
2. To a small quantity of residue add lead acetate solution. The yellow-coloured precipitate is formed. The addition of an
B. Sc. Part - I (Sem-II) Unit-IV (A) Phenols by Dr Pramod R Padolepramod padole
A) PHENOLS: Methods of formations a) from aniline & b) from cumene. Acidic character, Reaction of Phenols- a) Carboxylation (Kolbe’s reaction), b) Fries Rearrangement, c) Claisen Rearrengement and d) Reimer – Tiemann reaction.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
2. Introduction
• Flavonoids consist of a large group of
polyphenolic compounds belong to a class
of plant secondary metabolites having a
benzo-𝛾-pyrone structure and are
ubiquitously present in plants, fruits,flowers
vegetables and certain beverages..
• They are synthesized by phenylpropanoid
pathway.
• It is derived from latin word flavus meaning
yellow.
3. Use
Flavonoids are associated with a broad
spectrum of health-promoting effects
and are an indispensable component
in a variety of nutraceutical,
pharmaceutical, medicinal and
cosmetic applications.
4. HISTORY
• Flavonoids are a group of natural compounds with
variable phenolic structures and are found in plants.
• In 1930 a new substance was isolated from oranges.
• At that time it was believed to be a member of a new
class of vitamins and was designated as vitamin P.
• Later on it became clear that this substance was a
flavonoid (rutin)
• Till now more than4000 varieties of flavonoids have
been identified
7. Classification
Flavonoids can be subdivided into
different subgroups depending on
the carbon of the C ring on which
the B ring is attached and the
degree of unsaturation and
oxidation of the C ring
8. Classification
• Flavonoids in which the B ring is linked in position
3 of the C ring are called isoflavones.
• Those in which the B ring is linked in position 4
are called neoflavonoids,
• while those in which the B ring is linked in
position 2 can be further subdivided into several
subgroups on the basis of the structural features
of the C ring. These subgroups are: flavones,
flavonols, flavanones, flavanonols, flavanols or
catechins, anthocyanins and chalcones
15. • In plants, flavonoids are synthetized via phenyl
propanoid biosynthetic pathway and their
structural feature is a 2-phenyl-benzo-γ-pyrane
nucleus including two aromatic rings (A and B
rings) and a pyran heterocyclic ring (C ring).
• The A-ring originates from the cyclization of 3
molecules of malonyl CoA and it is linked to B-
ring, derived from phenylalanine, by a three-
carbon bridge (C-ring).
16. Flavones
• They have a double bond between positions 2
and 3
• A ketone in position 4 of the C ring.
• Most flavones have a hydroxyl group in
position 5 of the A ring,
• while hydroxylation in other positions, for the
most part in position 7 of the A ring or 3′ and
4′ of the B ring
17. Special Characteristics of Flavonoids:
• Flavonoids are one of the most essential non-
nitrogenous plant pigments.
• It is responsible for flower coloration by
producing yellow or red/blue pigmentation in
shoots, leaves, buds, petals, and fruits.
• This pigmentation is to attract pollinators to the
flowers.
• In some types of plants, flavonoids are involved in
UV filtration, symbiotic nitrogen fixation and
floral pigmentation.
19. Spectral Characteristics of Flavonoids.
• Studies on flavonoids by spectroscopy have
revealed that most flavones and flavonols
exhibit two major absorption bands:
• Band I (320–385nm) represents the B ring
absorption, while
• Band II (250–285 nm) corresponds to the A
ring absorption.
21. Band I and Band II reason
Band I peak in the 450-560 nm
region due to hydroxyl
cinnamoyl system of the B ring
and Band II peaks in the 240-
280 nm region due to the
benzoyl system of the A ring
22. Biogenesis of flavone
• From the biogenetic point of view the C15
carbon frame work of flavonoid can be divided
into two parts, one part consisting of six
carbon atoms which form the ring A.
• The other part consisting of nine carbon
atoms known as phenyl propanoid moiety.
• Ring A by acetate or polyketide route
• Ring B by shikimate pathway.
35. Presence of hydroxyl group and
methoxyl group
• Oxidation
• Acetylation
• Zerewitinoff determination
• Zeisel,’s reaction
36. Zerewitinoff determination
The Zerewitinoff determination or Zerevitinov
determination is a quantitative chemical test for
the determination of active hydrogens in
a chemical substance. A sample is treated with
the Grignard reagent, methylmagnesium iodide,
which reacts with any acidic hydrogen atom to
form methane. This gas can be determined
quantitatively. For example:
38. Zeisel’s reaction
• Zeisel test is a chemical test for the presence
of esters or ethers in a chemical substance.
• In a qualitative test a sample is first reacted
with a mixture of acetic acid and hydrogen
iodide in a test tube.
• The ensuing reaction results in the cleavage of
the ether or the ester into an alkyl iodide and
respectively an alcohol or a carboxylic acid.
39. • By heating this mixture, the gases are allowed to come
into contact with a piece of paper higher up the test
tube saturated with silver(II) nitrate. Any alkyl iodide
present will give a reaction with the mercury
compound to silver (II) iodide which has a red or yellow
color.
• The reaction can also be used to determine the
number of methoxy (-OCH3) groups,by distilling the
iodomethane into a solution of silver nitrate, which
precipitates silver iodide. By filtering and weighing this
precipitate it is possible to calculate the number
of iodine atoms and hence methoxy groups.
41. Reaction of isoflavone with KOH
alc.KOH
Boiling
O
O
OH
OH
+
OH
O
OH
Alc.KOH
O
OH
H +
O
OH OH
OH
Formic acid
P-hydroxy phenyl acetic acid
Resorcinol
P hydroxy phenyl acetic acid
42. References
• Shashank Kumar and Abhay K. Pandey
Chemistry and Biological Activities of
Flavonoids: An Overview Hindawi Publishing
Corporation The ScientificWorld Journal
Volume 2013, Article ID 162750, 16 pages
• http://dx.doi.org/10.1155/2013/162750.
• Prithviraj Karak BIOLOGICAL ACTIVITIES OF
FLAVONOIDS: AN OVERVIEW Karak, IJPSR,
2019; Vol. 10(4): 1567-1574.
43. • Pharmaceutical chemistry of natural product
by V.Alagarsamy Elsevier page no: 427-438.
• Chemistry of natural product by S.V.Bhat
Narosa publication 585
![Flavonoids
Prepared by
Dr. N.GOPINATHAN
ASSISTANT PROFESSOR
DEPARTMENT OF PHARMACEUTICAL CHEMISTRY
FACULTY OF PHARMACY
SRIHER [DU]
CHENNAI-116
TAMILNADU](https://image.slidesharecdn.com/flavonoids-200227075346/85/Flavonoids-1-320.jpg)
