英语翻译
ExperimentalSection
Synthesisof7/8-Hydroxycarbonylalloxazine(5).Toastirred
solutionof3,4-diaminobenzoicacid(3,3.04g,20mmol)in170
mLofaceticacidwereaddedboricacid(1.36g,22mmol)and
alloxane(4)monohydrate(3.36g,21mmol).Thereactionwas
stirredfor3hatroomtemperatureafterwhichtheprecipitated
productwasfilteredoffandwashed,firstwithaceticacidthenwith
diethylether,water,andlastdiethylether.Theproduct5(green
powder)wasisolatedina3:2ratioofthe7-and8-isomerin
quantitativeyield.Majorisomer:1HNMR(400MHz,DMSOd6)
ä12.02(s,1H),11.79(s,1H),8.29(d,J)1.9Hz,1H),8.18
(d,J)8.8Hz,1H),8.09(dd,J)1.9,8.8Hz,1H).Minorisomer:
1HNMR(400MHz,DMSO-d6)ä12.06(s,1H),11.80(s,1H),
8.55(d,J)2.0Hz),8.25(dd,J)2.0,8.8Hz,1H),7.90(d,J)
8.8Hz,1H).13CNMR(DMSO-d6,100MHz)forthemixtureä
167.0,167.0,160.8,160.8,150.7,150.7,148.6,148.1,145.4,142.5,
141.4,138.8,135.1,134.0,133.7,132.8,132.5,131.1,130.8,129.1,
128.0,127.9.
SynthesisofN1,N3-Dimethyl-7/8-methoxycarbonylalloxazine
(6).9Toastirredsolutionof7/8-hydroxycarbonylalloxazine(5)
(2.58g,10mmol)in500mLofdimethylformamide(DMF)were
addedpotassiumcarbonate(K2CO3)(4.70g,34mmol)andmethyl
iodide(2mL,32mmol).Thereactionmixturewasstirredovernight
(22h)afterwhichitwasfilteredthroughaglassfilterfunnelto
removeinorganicsalts.Theliquidswerecollectedandthesolvents
removedunderreducedpressure.Thesolidswerethensuspended
in500mLofchloroform(CHCl3)andextractedwith200mLof2
Mhydrochloricacid(HCl),200mLofdilutedbrine,andfinally
200mLofbrine.Theorganicphasewasdriedoversodiumsulfate
(Na2SO4)andafterfiltrationthesolventswereremovedandthe
productdriedundervacuum.Theproduct6wasisolatedin86%
yieldasayellowsolid.Theproductwasamixtureofthe
7-methoxycarbonylderivativeandthe8-me