Isoflavonoid

3-phenylchromen-4-one

3-phenylchroman (isoflavan) backbone of the isoflavanes

Isoflavonoids are a class of flavonoid phenolic compounds, many of which are biologically active. Isoflavonoids and their derivatives are sometimes referred to as phytoestrogens, as many isoflavonoid compounds have biological effects via the estrogen receptor.

Medically, isoflavonoids and related compounds have been used in many dietary supplements but the medical and scientific community is generally skeptical of their use. Recently, some natural isoflavonoids have been identified as toxins, including biliatresone which may cause biliary atresia when infants are exposed to the plant product.[1]

The isoflavonoid group is broad, and includes many structurally similar groups, including:

* isoflavones
* isoflavanones
* isoflavans
* pterocarpans[2]
* rotenoids

Isoflavonoids are derived from the flavonoid biosynthesis pathway via liquiritigenin or naringenin.[3]

## Chemical makeup[edit]

While flavonoids (in the narrow sense) have the 2-phenylchromen-4-one backbone, isoflavonoids have the 3-phenylchromen-4-one backbone with no hydroxyl group substitution at position 2 (case of the isoflavones) or the 3-phenylchroman (isoflavan) backbone (case of isoflavanes, such as equol).

## See also[edit]

* Daidzein
* Equol
* Flavonoid
* Genistein
* Glycitein
* Homoisoflavonoids, related molecules with a 16-carbon skeleton
* Isoflavone

## References[edit]

1. ^ Lorent, Kristin; Gong, Weilong; Koo, Kyung A.; Waisbourd-Zinman, Orith; Karjoo, Sara; Zhao, Xiao; Sealy, Ian; Kettleborough, Ross N.; Stemple, Derek L. (2015-05-06). "Identification of a plant isoflavonoid that causes biliary atresia". Science Translational Medicine. 7 (286): 286ra67. doi:10.1126/scitranslmed.aaa1652. ISSN 1946-6234. PMC 4784984. PMID 25947162.
2. ^ superpathway of pterocarpan biosynthesis (via formononetin) on metacyc.org
3. ^ "Isoflavonoid biosynthesis". BioSystems. U.S. National Library of Medicine.

* v
* t
* e

Xenoestrogens

Phytoestrogens|

| Flavanones|

* Hesperetin
* Liquiritigenin
* Naringenin
* Pinocembrin

|

Flavones|

* Acacetin
* 7,8-Dihydroxyflavone
* Mirificin

Prenylflavonoids|

* 8-Prenylnaringenin
* 6-Prenylnaringenin
* 8-Geranylnaringenin
* 6,8-Diprenylnaringenin
* Icaritin

Isoflavones|

* Biochanin A
* Daidzein
* Daidzin
* Formononetin
* Genistein
* Genistin
* Glycitein
* Ononin
* Prunetin
* Puerarin
* Tectorigenin

Isoflavanes|

* Equol (S-Equol)
* Glabridin

Dihydrochalcones|

* Phloretin
* Phlorizin

Isoflavenes|

Glabrene

Coumestans|

* Coumestan
* Coumestrol
* Desmethylwedelolactone
* Wedelolactone

Lignans|

* Enterodiol
* Enterolactone

Flavonolignans|

* Silybin
* Cinchonain-Ib

Flavonols|

* Quercetin

Others|

* Deoxymiroestrol
* Miroestrol
* Resveratrol
* α-Isosparteine

Mycoestrogens|

* Zearalanone
* Zearalenone
* α-Zearalanol (zeranol)
* α-Zearalenol
* β-Zearalanol
* β-Zearalenol

| Derivatives|

* D-Penicillamine

|

Synthetic|

* Alkylphenols
* Atrazine
* BHA
* Bisphenol A
* Bisphenol F
* Bisphenol S
* DDE
* DDT
* Dieldrin
* Dioxins
* Endosulfan
* Enzacamene
* Erythrosine
* Heptachlor
* Lindane
* Methoxychlor
* Nonylphenol
* Parabens
* PBBs
* PCBs
* Pentachlorophenol
* PHBA
* Phthalates
* Propyl gallate
* Perfluorinated compound

Metalloestrogens|

* Aluminium
* Antimony
* Arsenite
* Barium
* Cadmium
* Chromium
* Cobalt
* Copper
* Lead
* Mercury
* Nickel
* Selenite
* Tin
* Vanadate

* v
* t
* e

Types of flavonoids

Flavonoids|

| Anthoxanthins|

| Flavones|

* Apigenin, Chrysin, et.c.

|

Flavonols|

* Quercetin, Kaempferol, et.c.

Isoflavones|

* Daidzein, Genistein, Orobol et.c.

Neoflavonoids|

* Dalbergichromene

Flavans|

| Flavan|

* Luteoliflavan

|

Flavan-3-ols
(flavanols)|

* Catechin, Gallocatechol, et.c.

Flavan-4-ols
(flavanols)|

* Apiforol, Luteoforol, et.c.

Flavan-3,4-diols|

* Leucocyanidin, Leucodelphinidin, et.c.

Flavanones|

* Hesperidin
* Naringenin
* Eriodictyol

Flavanonols|

* Taxifolin
* Aromadendrin, et.c.

Anthocyanidins|

| 3-deoxyanthocyanidins|

* Cyanidin, Delphinidin, et.c.

|

3-hydroxyanthocyanidin|

* Apigeninidin, Guibourtinidin, et.c.

Aurones|

* Aureusidin
* Leptosidin

Chalcones|

| Chalcones|

* Butein, Isoliquiritigenin, et.c.

|

Dihydrochalcone|

* Phloretin

Miscellaneous|

* List of phytochemicals in food
* C-methylated flavonoids
* O-methylated flavonoids
* Furanoflavonoids
* Pyranoflavonoids
* Prenylflavonoids
* Methylenedioxy
* Castavinols

Flavonoid biosynthesis

* v
* t
* e

Types of isoflavonoids

Isoflavonoids:|

* Isoflavanes
* Isoflavandiols
* Isoflavenes
* Isoflavones
* Pterocarpans

Misc.|

* Pterocarpans
* Isoflavonoid biosynthesis

* v
* t
* e

GABA receptor modulators

Ionotropic|

| GABAA|

* Agonists: (+)-Catechin
* Bamaluzole
* Barbiturates (e.g., phenobarbital)
* Beta-Alanine
* BL-1020
* DAVA
* Dihydromuscimol
* GABA
* Gabamide
* GABOB
* Gaboxadol (THIP)
* Homotaurine (tramiprosate, 3-APS)
* Ibotenic acid
* iso-THAZ
* iso-THIP
* Isoguvacine
* Isomuscimol
* Isonipecotic acid
* Kojic amine
* L-838,417
* Lignans (e.g., honokiol)
* Methylglyoxal
* Monastrol
* Muscimol
* Nefiracetam
* Neuroactive steroids (e.g., allopregnanolone)
* Org 20599
* PF-6372865
* Phenibut
* Picamilon
* P4S
* Progabide
* Propofol
* Quisqualamine
* SL-75102
* Taurine
* TACA
* TAMP
* Terpenoids (e.g., borneol)
* Thiomuscimol
* Tolgabide
* ZAPA

* Positive modulators (abridged; see here for a full list): α-EMTBL
* Alcohols (e.g., drinking alcohol, 2M2B)
* Anabolic steroids
* Avermectins (e.g., ivermectin)
* Barbiturates (e.g., phenobarbital)
* Benzodiazepines (e.g., diazepam)
* Bromide compounds (e.g., potassium bromide)
* Carbamates (e.g., meprobamate)
* Carbamazepine
* Chloralose
* Chlormezanone
* Clomethiazole
* Dihydroergolines (e.g., ergoloid (dihydroergotoxine))
* Etazepine
* Etifoxine
* Fenamates (e.g., mefenamic acid)
* Flavonoids (e.g., apigenin, hispidulin)
* Fluoxetine
* Flupirtine
* Imidazoles (e.g., etomidate)
* Kava constituents (e.g., kavain)
* Lanthanum
* Loreclezole
* Monastrol
* Neuroactive steroids (e.g., allopregnanolone, cholesterol, THDOC)
* Niacin
* Niacinamide
* Nonbenzodiazepines (e.g., β-carbolines (e.g., abecarnil), cyclopyrrolones (e.g., zopiclone), imidazopyridines (e.g., zolpidem), pyrazolopyrimidines (e.g., zaleplon))
* Norfluoxetine
* Petrichloral
* Phenols (e.g., propofol)
* Phenytoin
* Piperidinediones (e.g., glutethimide)
* Propanidid
* Pyrazolopyridines (e.g., etazolate)
* Quinazolinones (e.g., methaqualone)
* Retigabine (ezogabine)
* ROD-188
* Skullcap constituents (e.g., baicalin)
* Stiripentol
* Sulfonylalkanes (e.g., sulfonmethane (sulfonal))
* Topiramate
* Valerian constituents (e.g., valerenic acid)
* Volatiles/gases (e.g., chloral hydrate, chloroform, diethyl ether, paraldehyde, sevoflurane)

* Antagonists: Bicuculline
* Coriamyrtin
* Dihydrosecurinine
* Gabazine (SR-95531)
* Hydrastine
* Hyenachin (mellitoxin)
* PHP-501
* Pitrazepin
* Securinine
* Sinomenine
* SR-42641
* SR-95103
* Thiocolchicoside
* Tutin

* Negative modulators: 1,3M1B
* 3M2B
* 11-Ketoprogesterone
* 17-Phenylandrostenol
* α5IA (LS-193,268)
* β-CCB
* β-CCE
* β-CCM
* β-CCP
* β-EMGBL
* Anabolic steroids
* Amiloride
* Anisatin
* β-Lactams (e.g., penicillins, cephalosporins, carbapenems)
* Basmisanil
* Bemegride
* Bicyclic phosphates (TBPS, TBPO, IPTBO)
* BIDN
* Bilobalide
* Bupropion
* CHEB
* Chlorophenylsilatrane
* Cicutoxin
* Cloflubicyne
* Cyclothiazide
* DHEA
* DHEA-S
* Dieldrin
* (+)-DMBB
* DMCM
* DMPC
* EBOB
* Etbicyphat
* FG-7142 (ZK-31906)
* Fiproles (e.g., fipronil)
* Flavonoids (e.g., amentoflavone, oroxylin A)
* Flumazenil
* Fluoroquinolones (e.g., ciprofloxacin)
* Flurothyl
* Furosemide
* Golexanolone
* Iomazenil (123I)
* IPTBO
* Isopregnanolone (sepranolone)
* L-655,708
* Laudanosine
* Leptazol
* Lindane
* MaxiPost
* Morphine
* Morphine-3-glucuronide
* MRK-016
* Naloxone
* Naltrexone
* Nicardipine
* Nonsteroidal antiandrogens (e.g., apalutamide, bicalutamide, enzalutamide, flutamide, nilutamide)
* Oenanthotoxin
* Pentylenetetrazol (pentetrazol)
* Phenylsilatrane
* Picrotoxin (i.e., picrotin, picrotoxinin and dihydropicrotoxinin)
* Pregnenolone sulfate
* Propybicyphat
* PWZ-029
* Radequinil
* Ro 15-4513
* Ro 19-4603
* RO4882224
* RO4938581
* Sarmazenil
* SCS
* Suritozole
* TB-21007
* TBOB
* TBPS
* TCS-1105
* Terbequinil
* TETS
* Thujone
* U-93631
* Zinc
* ZK-93426

|

GABAA-ρ|

* Agonists: BL-1020
* CACA
* CAMP
* Homohypotaurine
* GABA
* GABOB
* Ibotenic acid
* Isoguvacine
* Muscimol
* N4-Chloroacetylcytosine arabinoside
* Picamilon
* Progabide
* TACA
* TAMP
* Thiomuscimol
* Tolgabide

* Positive modulators: Allopregnanolone
* Alphaxolone
* ATHDOC
* Lanthanides

* Antagonists: (S)-2-MeGABA
* (S)-4-ACPBPA
* (S)-4-ACPCA
* 2-MeTACA
* 3-APMPA
* 4-ACPAM
* 4-GBA
* cis-3-ACPBPA
* CGP-36742 (SGS-742)
* DAVA
* Gabazine (SR-95531)
* Gaboxadol (THIP)
* I4AA
* Isonipecotic acid
* Loreclezole
* P4MPA
* P4S
* SKF-97541
* SR-95318
* SR-95813
* TPMPA
* trans-3-ACPBPA
* ZAPA

* Negative modulators: 5α-Dihydroprogesterone
* Bilobalide
* Loreclezole
* Picrotoxin (picrotin, picrotoxinin)
* Pregnanolone
* ROD-188
* THDOC
* Zinc

Metabotropic|

| GABAB|

* Agonists: 1,4-Butanediol
* 3-APPA
* 4-Fluorophenibut
* Aceburic acid
* Arbaclofen
* Arbaclofen placarbil
* Baclofen
* BL-1020
* GABA
* Gabamide
* GABOB
* GBL
* GHB
* GHBAL
* GHV
* GVL
* Isovaline
* Lesogaberan
* Phenibut
* Picamilon
* Progabide
* Sodium oxybate
* SKF-97,541
* SL 75102
* Tolgabide
* Tolibut

* Positive modulators: ADX-71441
* BHF-177
* BHFF
* BSPP
* CGP-7930
* CGP-13501
* GS-39783
* rac-BHFF
* KK-92A

* Antagonists: 2-Hydroxysaclofen
* CGP-35348
* CGP-46381
* CGP-52432
* CGP-54626
* CGP-55845
* CGP-64213
* DAVA
* Homotaurine (tramiprosate, 3-APS)
* Phaclofen
* Saclofen
* SCH-50911
* SKF-97541

* Negative modulators: Compound 14

|

See also
Receptor/signaling modulators
GABAA receptor positive modulators
GABA metabolism/transport modulators
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template
*[GABA]: γ-Aminobutyric acid
*[GABAA]: γ-Aminobutyric acid A receptor
*[GABAA-ρ]: γ-Aminobutyric acid A-rho receptor
*[GABAB]: γ-Aminobutyric acid B receptor