
anomeric prabhavam

jaiva rasathanthrathil, anomeric prabhavam allengil edward-lemiax prabhavam oru steeriyo electronic efakttaanu, ithu oru cyclohexane valayathinullil oru hetteroaattathinaduthu heteroaattomik pakarakkaarude pravanathaye vivarikkunnu, sterik parigananakalil ninnu prathekshikkunna thadassamillaatha "bhoomadhyarekha" ooriyanteshanu pakaram "axial" ooriyanteshan thiranjedukkunnu. eee prabhavam aadyam pyranos valayangalil jeey nireekshichirunnu. tii. 1955ll carbohydrate rasathanthram padikkumbol edward.
anomeric ephakt" enna padam 1958-ll avatharippikkappettu. oru pyranosinte ettavum kuranja samkhyayulla ring kaarban, "anomeric" kaarban ennu nirddeshikkaan upayogikkunna padatthil ninnaan eee peru vannath. anomeric carbonile konfigareshanil maathram vyathyasamulla isomerukale "anomerukal" ennu vilikkunnu. - glucopyranosinte anomerukal diasteriomerukalaanu, "beetta" anomerinu madhyarekhayilekku oru ooo group undu, aaa groupinu aaa ooo group akshaparamaayi thaazhekku choondikkaanikkunnu.
onno athiladhikamo otta jodikalulla oru hetteroaattam aaya sii-vaii-sii-ex enna pothuvaaya soothravaakyamulla eathu cyclohexylileco leanier systethilekko anomeric ephakt saamaanyavalkkarikkam, ivide onno athiladhikamo otta jodikalulla oru hetteroaattam aanu, koodaathe ex oru electronegative aattam allengil group aanu. panchasaarayude kaaryatthil anomeric efakttinte vyaapthi ekadesham 1-2 kiloo kalori/moll aayi kanakkaakkappedunnu, pakshe oro thanmathraykkum ithu vyathyasthamaan.
melpparanja saahacharyathil, cyclohexane valayathile (mukalil) methoxy group bhoomadhyarekhayude sthaanam eshtappedunnu. ennirunnaalum, tetrahydropyran valayathil (thaazhe), methoxy group aksheeya sthaanamaanu eshtappedunnathu. kaaranam cyclohexane valayathil, vaii = kaarban, ithu oru hetteroaattam allah, athinaal anomeric prabhavam nireekshikkappedaathinal steriks nireekshicha pakarakkaarante sthaanathu aadhipathyam pulartthunnu. tetrahydropyran valayathil, oru heteroaattamaaya y = ooksijan, athinaal anomeric prabhavam nireekshicha pakarakkaarante sthaanam sambhavana cheyyukayum sthirappeduthukayum cheiyunnu. rund saahacharyangalilum, x = oom.
vaii = ooksijan aayirikkumbozhaanu anomeric prabhavam palappozhum nireekshikkappedunnathu, ennaal naitrajan, sulfur, phoosphoorus thudangiya valayathil hetteroaattangal vahikkunna mattu eaka jody jodiyilum ithu kaanaan kazhiyum. 
anomeric prabhavam sthirathaykku kaaranamakunna krithyamaaya reethi vivaadathinte oru poyintaanu, athu vishadeekarikkaan niravadhi sidhaanthangal nirddeshikkappettittund.
bhauthika vishadeekaranavum vivaadangalum.
anomeric efakttinte bhauthika kaaranam poornnamaayum manassilakkiyitla. bhaagikamaayi vairudhyamulla niravadhi vishadeekaranangal nalkappedukayum vishayam ippozhum pariharikkappedaathirikkum cheythu.
hyperconjugation.
chaakrika thanmathrakal.
endocyclic hetteroaattamile (panchasaara valayathinullil) pankidaattha electron jodiyum aksheeya (exocyclic) sii-ex bondinte σ * bhramanapathavum thammil sthirathayulla oru prathipravartthanam (hyperconjugation) undennathaanu vyaapakamaayi amgeekarikkappetta oru vishadeekaranam. ithu thanmatra ekajodi electronukalaaya aantiperiplaanarine (180°) exocyclic sii-x σ bondilekku vinyasikkaan kaaranamaakunnu, ithu sisttathinte mothatthilulla oorjjam kuraykkukayum kooduthal sthiratha undaakkukayum cheiyunnu.
thanmaathrakalile aattangalude kwaandam sidhaanthathil ninnulla phalangale adisthaanamaakki eee hyperconjugation modalinte saadhuthaye chila rachayithakkal chodyam cheiyunnu. anomeric efakttukalekkurichulla mikka padanangalum saidhaanthika swabhaavamullavayaanengilum, eee sidhaantham nirddeshikkunna asattalukalile electron saandrata punarvitharanam ariyappedunna pareekshanathmaka rasathanthravumaayi, prathyekichu monosacrarideukalude rasathanthravumaayi poruthappedunnilla ennathinte adisthaanathil enn-sii * (hyperconjugation) sidhaanthavum vyaapakamaayi vimarshikkappettittundu.
asyclic thanmathrakal.
anomeric efakttinte mattoru roopamaaya hetteroaattangal adangiyirikkunna asyclic thanmaathrakalilum hyperconjugation kaanapedunnu. oru thanmaathraykk eaka jody electronukalulla oru aattam undengil, aduthulla aattathin σ * bhramanapathathilekku electronukale sweekarikkaan kazhiyumenkil, hyperconjugation sambhavikkunnu, ithu thanmatra sthirappeduthunnu. ithu oru "noow boond" anurananm roopappeduthunnu. eee bhramanapatha ovarlaappu sambhavikkunnathin, mikka hetteroaattamukalkkum "trans", "trans" roopeekaranamaanu munganana nalkunnathu, ennirunnaalum dimethoximethainil sthiratha sambhavikkunnathin, "trans", "trans" roopeekaranathekkaal (kooduthal sthirathayulla) oorjjam ekadesham 3-5 kiloo kalori/moll kuravaanu, ithu panchasaarayile falathekkaal eratti valuthaanu, kaaranam rund rott bondukal undu (athinaal ithu rund bondukalkkum chuttum "trans" allengil iruvarkkum chuttum "gaush" aanu).
dvidhruva laghookaranam.
anomeric efakttinulla mattoru sveekaaryamaaya vishadeekaranam, bhoomadhyarekhayude krameekaranatthil rund hetteroaattamukalum bhaagikamaayi vinyasichirikkunna dvidhruvangalundu, athinaal parasparam pinthirippikkunnu ennathaanu. ithinu vipareethamaayi aksheeya krameekaranatthinu eee dvidhruvangal ekadesham ethirvashathaanu, athinaal kooduthal sthirathayullathum thaazhnnathumaaya oorjjaavasthaye prathinidheekarikkunnu.
hyperconjugation dvidhruva minimisation (iii)-konformeshanekkaal ishtappetta (isad)-esttarukal roopappeduthunnathinu kaaranamaakunnu. (z) roopeekaranathil alfa ooksijanile eaka jody electronukalkku ayal σ * c-o bhramanapathathilekku sambhavana cheyyaan kazhiyum. koodaathe, dvidhruvam (z)-roopeekaranathil minimise cheyyukayum (e)-roopeekaranathil paramavadhi vardhippikkukayum cheiyunnu. 
enn-enn repulsionukalum sii-echu hydrajan bonding.
2-methoxipirente anomeric kendratthile ooksijanukalile eaka jody electronukal kaanikkukayaanengil, anomerukalude roopeekaranangalekkurichula oru hraswa parisodhana velippeduthunnathu β-anomerinu ellaayppozhum kuranjathu oru jody grahanam (coplaner 1,3-prathipravartthanam) otta jody undennu, eee n-n vikarshanam uyarnna oorjja saahacharyamaan. maruvashathu, α-anomerinu n-n repulsionukalillaatha roopeekaranangalundu, ithu exo-anomeric roopeekaranathil sariyaanu. β-anomeril kaanapedunna oorjjaparamaayi prathikoolamaaya n-n vikarshanavum, axial h-5 umm axial α-anomeric substituventile (c-h/n hydrajan boond) eaka jody electronukalum thammilulla oorjjaparamaayi anukoolamaaya hydrajan bond, anomerukal thammilulla oorjjaparamaaya vyathyasamaaya anomeric ephakt kanakkiledukkaan nirddeshikkappettittund. anomeric efakttinaayi prathyekamaayi paaraameettar cheyyaatha molecular mechanics prograam strum3dii, anomeric efakttinulla dvidhruva sambhavanakal (praadhamikamaayi enn-enn repulsion, sii-echu hydrajan bonting enniva mukalil charcha cheythava) ekadesham 1.5 kiloo kalori/moll aanennu kanakkakkunnu.
swaadheenangal.
oru thanmaathrayude itharathilulla sthirathaykkulla pothuvaaya vishadeekaranamaanu anomeric prabhavam, athesamayam sthirathayude tharatheyum alavineyum parishodhikkunna pakarakkareyum padikkunna laayakatheyum baadhichekkaam.
pakara prabhavam.
oru adacha samvidaanathil, cyclohexane allengil tetrahydropyran valayathil (y = ooksijan) vyathyastha pakarakkarkkulla anomeric efakttil vyathyasam nireekshikkappedunnu. x = oh aayirikkumbol, munbu vishadeekarichathupole, pothuvaaya anomeric prabhavam kaanaan kazhiyum. x = cn aayirikkumbol, cyclohexane valayathil bhoomadhyarekhayude sthaanam thiranjedukkumbol athe phalangal kaanapedunnu, ennaal tetrahydropyran valayathil aksheeya sthaanam thiranjedukkunnu. ithu anomeric ephakt stabilisationumaayi poruthappedunnu. x = f aayirikkumbol, rund valayangalilum anomeric prabhavam nireekshikkappedunnu. ennirunnaalum, x = nh2 aayirikkumbol, anomeric ephakt stabilisation nireekshikkappedaathinal rund sisttangalum bhoomadhyarekhayude sthaanam eshtappedunnu. ithu steriksum reverse anomeric ephakt ennu vilikkunna oru phalavum moolamaanu (chuvade kaanuka).
layaka prabhavam.
hyperconjugation sidhaanthathekkurichulla oru saadhaarana vimarsanam, pakaram tetrahydropyran thanmathrakal dhruva layakangalil sthaapikkumbol anomeric prabhavam nireekshikkappedaathinthi kaaranam vishadeekarikkunnathil paraajayappedunnu ennathaanu, koodaathe bhoomadhyarekhayude sthaanam veendum munganana nalkunnu. ennirunnaalum, hyperconjugation sisttathile laayakathe aashrayichirikkunnuvennu theliyikkappettittund. mukalil vivaricha oro pakara samvidaanangalum vathaka ghattathil pareekshichu (i.iii. laayakamillathe) jaleeya laayaniyil (i.iii. dhruveeya layakam). x = f aayirikkumbol, rund maadhyamangalilum anomeric prabhavam nireekshikkappedukayum aksheeya sthaanathinu ellaayppozhum munganana nalkukayum cheythu. hyperconjugeshanaanu ithinu kaaranam. x = oh allengil cn aayirikkumbol, axial sthaanathinu munganana nalkumbol vathaka ghattathil anomeric prabhavam kaanapettu. ennirunnaalum, jaleeya laayanikalil, rund pakarakkaarum madhyarekhayude sthaanamaanu thiranjedutthathu. aksheeya sthaanathulla pakarakkaran dhruva laayakavum upayogichu kooduthal electrostaattik vikarshanangal undenna vasthuthayaan ithinu kaaranam, ithu bhoomadhyarekhayude sthaanathinu munganana nalkunnu. x = nh2 aayappol, veendum, anomeric prabhavam nireekshikkappedaathe bhoomadhyarekhayude sthaanam ellaayppozhum munganana nalkappettu.
anomeric efakttine marikadakkuka.
anomeric prabhavam thanmaathrakalude sthirathaykku kaaranamaakumenkilum, athinte sthirathaykku oru vyaapthiyund, chila sandarbhangalil kooduthal asthirappeduthunna mattu falangalaal eee moolyam marikadakkaan kazhiyum.
spirockettalukalude udaaharanathil, mukalil idathuvashathulla ooriyanteshan rund thavana hyperconjugative anomeric ephakt vazhi sthiratha kaanikkunnu, angane thanmaathrayude ooriyanteshane valareyadhikam sthirappeduthunnu. mukalil valathuvashathulla ooriyanteshan eee hyperconjugative anomeric stabilisation orikkal maathrame kaanikkoo, ithu kuranja mungananayulla gadanayaayi maarunnu. ennirunnaalum, spirockettal nattellilekku pakarakkaare cherkkumbol, kooduthal mungananayulla ghadana maattaan kazhiyum. thaazhathe idathuvashathu kaanunnathupole, spirockettal nattellilekku oru valia pakarakkaaran cherkkumbol, eee valia pakarakkaaran, r, aksheeya sthaanathu undaakunnathil ninnulla strain thanmatra valareyadhikam asthirappeduthunnu. thaazhe valathuvashathulla thanmathrayil, r ippol madhyarekhayude sthaanathaanu, ithu thanmathrayil asthirathaykku kaaranamakunnilla. athinaal, pakarakkaarillathe, idathu vashath uyarnna santhulithaavasthaykkulla prathikaranam anukoolamaanu, athesamayam valath vashath thaazhnna santhulithaavastha anukoolamaanu, valia, asthirappeduthunna pakarakkaaran cherkkunnathil ninnu.
exo anomeric prabhavam.
anomeric efakttinte vipuleekaranamaaya exo anomeric ephakt, gauchu conformation sweekarikkunnathinaayi oru ringle ninnu varunna pakarakkaarude mungananayaan, athesamayam steriks oru aanti periplanar konformeshanaanu munganana nalkunnathennu soochippikkunnu. 
2-methoxytetrahydrone ithinu oru udaaharanamaanu. anomeric prabhavam pravachikkunnathupole, methoxy pakarakkaaran aksheeya roopeekaranathinu kooduthal munganana kaanikkunnu. ennirunnaalum, methoxy pakarakkaran valayavum thammilulla sii-oo bondinekkurichulla bhramanam kaaranam yadhaarthathil onniladhikam saadhyamaaya akshaghadanayundu. reverse anomeric efakttinte thathwangal oraal prayogikkumbol, gosh konformarinu munganana nalkumennu pravachikkaan kazhiyum, ithu mukalilulla chithratthil mukalil idathu konformeshanaanu ettavum nallathennu soochippikkunnu. eee pravachanatthe pareekshanathmaka thelivukal pinthunaykkunnu. koodaathe, gosh sthaanathinaayulla eee munganana ippozhum bhoomadhyarekhayude roopeekaranathil kaanapedunnu.
reverse anomeric prabhavam.
eee padam bhoomadhyarekhayude roopeekaranathinu positteev charjju cheytha naitrajan pakarakkaarude vyakthamaaya munganana soochippikkunnu, ooksijan polulla electronegative aattam adangiya valayangalil saadhaarana sterik edapedalukal pravachikkunnathinappuram. bhagika positteev chaarjukalulla carbonukal adangiyirikkunna pakarakkar ore phalam prakadippikkunnathu kanunnilla. reverse anomeric efakttinulla saidhaanthika vishadeekaranangalil oru electrostaattik vishadeekaranavum anomeric kaarban, ooksijan loonn jody ennivayude sp3 electronukalude delocalisation ulppedunnu. ithu oru yadhaartha prathibhaasamaano allayo ennathinekkurichu chila charchakal nadakkunnundu. ithu report cheyyappetta pakarakkar adangiyirikkunna naitrajan valare valuthaanu, ithu sterik balkkinte saadhaarana phalangalum reverse anomeric efakttum undengil verthirikkunnathu budhimuttaakkunnu. udaaharanathinu, chuvade kaanichirikkunna thanmathrayil, pyridinium pakarakkaaran bhoomadhyarekhayude sthaanam shakthamayi eshtappedunnu, kaaranam sterik gadakangal pravachikkum, ennaal yadhaarthathil eee roopeekaranathinu pravachichathinekkaal sakthamaaya munganana kaanikkunnu, ithu reverse anomeric prabhavam sambhavana cheiyunnuvennu soochippikkunnu.
mettalo-anomeric prabhavam.
10, 11, 12 grouppukalil ninnulla vaikiyulla parivartthana lohangal anomeric carbonil sthaapikkumbol sakthamaaya aksheeya mungananakal kaanikkunnu. mettalo-anomeric prabhavam ennu vilikkappedunna eee prathibhasam uthbhavikkunnath ooksijanum mattu hetteroaattamukalum thammilulla hyperconjugative edapedalukal sthirappeduthunnathil ninnaan, otta jody, nalla sweekarthaakkalaayi pravartthikkunna sii-emm aanti-bonting oorbittalukal. m-ch2-or enna pothuvaaya soothravaakyamulla samyukthangalude synclinal konformarukalude thermodynamic stabilisationaanu generalised mettalo-anomeric ephakt. lohathilum electronic konfigareshanilum gadippichirikkunna ligandukal aksha/madhyarekha mungananakale swaadheenikkaam. pothuve paranjaal, groupile bharam kuranja moolakathil ninnu bharam koodiya moolakathilekku neengumbol mettalo-anomeric efakttinte vyaapthi vardhikkunnu. koodaathe, uyarnna ooksideshan avasthakal axial/synclinal konformarukale anukoolikkunnu.
synthetic aaplikkeshanukal.
anomeric prabhavam synthetic aayi kanakkiledukkunnu. panchasaara, panchasaara, carbohydrate rasathanthram ennivayil ithu kandethiyathinal anomeric efakttinte ettavum saadhaaranamaaya synthetic upayogangalilonnaan. udaaharanathinu, coinigs-norr glycosidation anomeric prabhavam moolam uyarnna diasterioselectivile oru α-allengil β-allengil groupine instaal cheiyunnu. anomeric efakttine marikadakkunna coinigs-norr glycosidation vazhi samanvayippikkunna chila ulppannangalaanu sophorolipid laakton, (+)-lepisidine eiii, (−)-lithospermoside enniva.