《糖生物学》课程教学课件（讲稿）07 rxns of hydroxyl groups-2

Lecture 7.1 Rxns of hydroxygroups-2

Lecture'7.1'Rxns'of'hydroxyl' groups72

1.Cyclic acetal formation:5-ring vs 6-ringOHOHHO(CH2)(CH2)Sn1processCH2)OHR-+ H20(CH2)nRcyclic acetal

1.#Cyclic#acetal#forma0on:#54ring#vs#64ring#

MeOH+HOOHMeHO（HMe)Me(H+OOHMeOMeHOH+HOOHHOPhHHOHPh

2.Acetonide protection of carbohydrate hydroxyl groupsHOHOHHMeo)+oMetOMeMeO4HOOMeOMeMeoOMeHOHOOH'OHHOH+OH

2.#Acetonide#protec0on#of#carbohydrate#hydroxyl#groups#

2.1 Rxn of glucose with acetone and acidHOOHH+H+HOHOOH0HO''OHHOHOOHOHgluofuranoseglucopyranosediacetoneglucose

2.1#Rxn#of#glucose#with#acetone#and#acid#

2.2 Rxn of galactose with acetoneandacidOHHCH+HOHO'OHOHdiacetonegalactosegalactopyranose

2.2#Rxn#of#galactose#with#acetone#and#acid#

2.3Rxnofmannosewithacetoneand acidHOOhH+H+HOHOIOH?HOOHOHHOOHOHmannopyranosemannofuranosediacetonemannose

2.3#Rxn#of#mannose#with#acetone#and#acid#

3.BenzylideneprotectionofcarbohydratehydroxylgroupsHOHMeOOMePh0PhH福OHOH+OHOHOMeOMePhHOH.OHCMeOOMeHPhHOHOH+OHOHOMeOMe

3.#Benzylidene#protec0on#of#carbohydrate#hydroxyl#groups#

4.Butane diacetal protection of diolsHOHOMeOHOMeOHOHOMe0MeoH+OOMeSMeSMeOHOMeOH0OMeSMe

4.#Butane#diacetal#protec0on#of#diols

5.Cyclicacetalhydrolysis:deprotectionofcarbohydratehydroxylgroupsHOAcOHHO"H20HOHO

5.#Cyclic#acetal#hydrolysis:#deprotec0on#of#carbohydrate## hydroxyl#groups#