Synthesis of 2-amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino- 2-deoxy-β-D-galactopyranosides: Using various 2-deoxy-2-phthalimido-D- galactopyranosyl donors and acceptors

1914

Veselý, Ledvina, Jindřich, Trnka, Šaman:

SYNTHESIS OF 2-AMINO-2-DEOXY-β-D-GALACTOPYRANOSYL-

(1→4)-2-AMINO-2-DEOXY-β-D-GALACTOPYRANOSIDES:

USING VARIOUS 2-DEOXY-2-PHTHALIMIDO-D-GALACTOPYRANOSYL

DONORS AND ACCEPTORS

3a

Jan VESELÝ^1a, Miroslav LEDVINA^1b,*, Jindřich JINDŘICH^2a, Tomáš TRNKA and

2b

David ŠAMAN

a

Department of Organic Chemistry, Charles University, Albertov 2030, 128 40 Prague 2,

Czech Republic; e-mail: jxvesely@natur.cuni.cz, jindrich@natur.cuni.cz, trnka@natur.cuni.cz

Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic,

Flemingovo nám. 2, 166 10 Prague 6, Czech Republic; e-mail: ledvina@uochb.cas.cz,

saman@uochb.cas.cz

1

2

3

b

1

2

Received Jun e 2, 2004

Accepted July 25, 2004

Dedicated with due respect to Professor Miloslav Černý on the occasion of his 75th birthday in

recognition of his outstanding contributions to carbohydrate chemistry.

A system atic study is presen ted of th e efficien cy of th e m ost com m on glycosylation m eth -

ods usin g stan dard 2-deoxy-2-ph th alim idogalactopyran osyl don ors eth yl 4-O-acetyl-3,6-di-O-

ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (3a), 4-O-Acetyl-3,6-di-O-ben zyl-

2-deoxy-2-ph th alim ido-β-D-galactopyran osyl brom ide (4), 4-O-acetyl-3,6-di-O-ben zyl-2-

deoxy-2-ph th alim ido-β-D-galactopyran osyl fluoride (5b ), O-(4-O-acetyl-3,6-di-O-ben zyl-2-

deoxy-2-ph th alim ido-β-D-galactopyran osyl) trich loroacetim idate (7) an d eth yl 3,6-di-O-

ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (8), pen t-4-en yl 3,6-di-O-ben zyl-

an d 3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (10a) an d (10b) an d

pen t-4-en yl 3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-4-O-(trim eth ylsilyl)-β-D-galactopyran -

oside (11) as glycosyl acceptors in th e syn th esis of 2-am in o-2-deoxy-β-D-galactopyran osyl-

(1→4)-2-am in o-2-deoxy-β-D-galactopyran osides 12, 16a an d 17a. It was foun d th at due to a

low reactivity of th e axial OH(4) group of glycosyl acceptors, disacch arides 16b an d 17b

with α(1→4) bon d were also form ed. Th e un expected in term olecular m igration of eth yl-

sufan yl group from th e reducin g en d of glycosyl acceptor 8 th e reducin g en d of th e acti-

vated form of glycosyl don or 4 in th e glycosylation step to give eth ylsulfan yl derivative 3a

was proved. For preparation of th e glycosyl don ors an d glycosyl acceptors with galacto con -

figuration an approach based on epim erization of 4-O-m esyl derivatives of appropriate

syn th on s with gluco con figuration 2a an d 2b was em ployed.

Keyw ord s: Carboh ydrates; Oligosacch arides; Am in osugars; D-Galactosam in e; Ph th alim ide;

Glycosyl don ors; Glycosyl acceptors; Glycosylation s; Peptidoglycan ; Glycoprotein s.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

doi:10.1135/cccc20041914

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1915

Th e β(1→4)-lin ked 2-am in o-2-deoxy-D-h exopyran ose m oieties are fre-

quen tly occurrin g structural un its in various biologically im portan t oligo-

sacch arides an d th eir glycocon jugates, wh ich h ave m ultiple biological fun c-

tion s an d activities, such as a play a key role in m olecular recogn ition an d

in teraction s of th e cell–cell, cell–bacteria, an d cell–virus types^1–3. In con -

trast to th e large n um ber of works devoted to th e syn th esis of oligosacch a-

rides with β(1→4)-lin ked 2-am in o-2-deoxy-D-glucopyran ose un its, th e syn -

th esis of an alogous oligosacch arides with β(1→4)-lin ked 2-am in o-2-deoxy-

D-galactopyran ose un its h as received on ly little atten tion so far. Th e

β(1→4)-lin ked N-acetylglucosam in e m oieties form e.g. an im portan t struc-

tural polysacch aride ch itin ⁴, glycan part of peptidoglycan of bacterial cell

walls^5,6as well as th e reducin g en d of glycan residues of N-glycoprotein s³.

A system atic study devoted to th e use of th e m ost com m on glycosylation

m eth ods for th e form ation of 1,2-trans-glycosidic bon d in th e syn th esis of

oligosacch arides with β(1→4)-lin ked 2-am in o-2-deoxy-D-glucopyran ose

un its was reported by Paulsen et al.⁷Th e β(1→4)-lin ked N-acetylgalactos-

am in e to 3-O-sialosyl-β-D-galactopyran oside un it con stitutes a core un it of

gan gliosides^8,9. Due to th e problem of form ation of β(1→4) glycosidic bon d

between two D-galactosam in e un its on ly on e article related to th is topic de-

scribin g syn th esis of gan glioside lactam s (i.e., stable an alogs of gan glioside

lacton es) was publish ed. Th is syn th esis is based on th e glycosylation of

2-am in o-2-deoxy-3-O-(sialosyl-1′,2′-lactam )-β-D-galactopyran oside subun it

or 2-azido-2-deoxy-3-O-sialosyl-β-D-galactopyran oside subun it as glycosyl

acceptor in position OH(4) with peracetylated 2-deoxy-2-ph th alim ido-

D-galactopyran osyl brom ide as glycosyl don or¹⁰. Oligosacch arides con sist-

in g of β(1→4)-lin ked 2-am in o-2-deoxygalactopyran ose un its are a group of

com poun ds h avin g a sign ifican t poten tial from both th e syn th etic an d bio-

logical poin ts of view. Th e 2-am in o-2-deoxy-β-D-galactopyran ose un its

h ave equatorially orien ted glycosidic bon d an d axially orien ted C(4)–O

bon d (i.e., in verted con figuration at both lin kage cen ters in com parison to

th e α-D-glucopyran ose un its, form in g cyclodextrin m olecules) an d so th ey

satisfy th e basic criteria for cyclization ¹¹. Oligosacch arides con sistin g of

β(1→4)-lin ked 2-acetam ido-2-deoxy-D-galactopyran ose un its also seem to

be poten tial m im ics of n atural ligan ds for activated receptor of NK (n atural

killer) cells, takin g in to accoun t th e fact th at th e bin din g activity of

N-acetyl-D-galactosam in e is h igh er th an N-acetyl-D-glucosam in e an d in th e

case of ch itooligom ers th is activity in creases with elon gation of th e

sacch aride ch ain ¹². Th e above m en tion ed facts m otivated us to focus our

atten tion on th e problem of syn th esis of oligosacch arides con sistin g

β(1→4)-lin ked 2-acetam ido-2-deoxy-D-galactopyran ose un its.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1916

Veselý, Ledvina, Jindřich, Trnka, Šaman:

RESULTS AND DISCUSSIONS

In th e syn th esis of an oligosacch aride con sistin g from β(1→4)-lin ked

2-am in o-2-deoxy-D-galactopyran ose un its we were con fron ted with th e

problem of stereoselective form ation of 1,2-trans-glycosidic bon d between

glycosyl don or an d glycosyl acceptor bearin g a free axially orien ted

OH group in position 4. A large n um ber of procedures for th e syn th esis of

1,2-trans-di- an d oligosacch arides are described. For th e 1,2-trans-glycosidic

lin kin g of 2-am in o-2-deoxyh exopyran oside residue, th e Koen igs–Kn orr,

oxazolin e an d ph th alim ide m eth ods are m ost often used^3,13,14. Th e

ph th alim ide m eth od is th e m ost preferred, because 2-deoxy-2-ph th alim ido-

h exopyran oses with h alogen , trich loroacetim idate or alkylsulfan yl group at

C-1 seem to be th e m ost efficien t don ors an d sh ow th e h igh est stereo-

selectivity^3,7. Th e axially orien ted OH(4) group on th e galactopyran ose skel-

eton is in gen eral foun d to be th e least reactive¹⁵. Th us, we were been

prom pted to m ake a system atic com parative in vestigation of th e m ost

widely used glycosylation m eth ods usin g th e syn th esis of m odel disac-

ch arides.

For th e preparation of appropriate glycosyl don ors an d acceptors of

galacto con figuration , th e approach based on th e in version of con figuration

at C-4 of th e correspon din g syn th on s with gluco con figuration ^16–18was ap-

plied (Sch em e 1). We used th e m esyl group as a leavin g group an d sodium

acetate as a n ucleoph ile, in stead of a com bin ation of trifluorom eth an e-

sulfon yl group with tetrabutylam m on ium or cesium acetate^16–18. Th e m ore

stable 4-O-m esyl derivatives 2a an d 2b (in con trast to an alogical 4-O-

trifluorom eth an esulfon yl derivatives) can be isolated an d are useful syn -

th on s for reaction s with oth er n ucleoph iles, wh ich give th e correspon din g

sacch aride un its with galacto con figuration . Eth yl 3,6-di-O-ben zyl-2-deoxy-

4-O-m esyl-2-ph th alim ido-1-th io-β-D-glucopyran oside (2a) an d eth yl 3-O-

allyl-6-O-b en zyl-2-d eo xy-4-O-m esyl-2-p h t h alim id o -1-t h io -β-D-glu co-

pyran oside (2b) were obtain ed by th e reaction of eith er eth yl 3,6-di-O-

ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside^19–21(1a), or eth yl

OBn

AcO

RO

O

b

O

a

HO

RO

MsO

RO

SEt

NPht

1a, R= Bn

1b, R=All

2a, R=Bn

2b, R=All

3a, R=Bn

3b, R=All

a) MsCl, pyridine; b) NaOAc, DMSO

Ms = mesyl; Pht = phthaloyl

SCHEME 1

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1917

3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside^18,20

(1b) with m eth an esufon yl ch loride in pyridin e. Mesylates 2a an d 2b upon

treatm ent with anhydrous sodium acetate in dry dim ethyl sulfoxide at 130 °C,

afforded th e key com poun ds eth yl 4-O-acetyl-3,6-di-O-ben zyl-2-deoxy-2-

ph th alim ido-1-th io-β-D-galactopyran oside (3a) an d eth yl 4-O-acetyl-3-O-

allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (3b),

respectively, in very good yields.

Th e attractive feature of th ioglycosides in oligosacch aride syn th esis is

th at th ey can be utilized directly as glycosyl don ors by activation via sul-

fon ium ion or readily con verted in to oth er glycosyl don ors used in m ost

com m on glycosylation m eth ods²²(i.e., glycosyl brom ides, fluorides²³

,

glycosyl trich loroacetim idates²⁴an d pen t-4-en yl (Pen t) glycosides). Th e

β-an om er of glycosyl brom ide 4 was obtain ed by th e reaction of eth yl

th ioglycoside 3a with brom in e in dich lorom eth an e (Sch em e 2). Th e reac-

tion of eth yl th ioglycoside 3a with N-brom osuccin im ide (NBS) an d dieth yl-

am in osulfur trifluoride (DAST) in dich lorom eth an e afforded a m ixture of α-

an d β-glycosyl fluorides 5a an d 5b, in th e 1:15 ratio, wh ich was separated

by ch rom atograph y on a silica gel colum n . Th e β-an om er of trich loro-

acetim idate 7 was prepared from eth yl th ioglycoside 3a by splittin g off th e

eth ylsulfan yl group with N-iodosuccin im ide (NIS) in a water–aceton e m ix-

ture, to yield 6, wh ich was th en con verted to 7 by usin g a m odified litera-

ture²⁵procedure treatm en t with trich loroaceton itrile in th e presen ce of

1,8-diazabicyclo[5.4.0]un dec-7-en e (DBU) in toluen e. Th e silver perch lorate

prom oted reaction of glycosyl brom ide 4 with pen t-4-en -1-ol in dich loro-

m eth an e afforded pen t-4-en yl glycoside 9a. Th e pen t-4-en yl glycoside 9b

was prepared directly from eth yl th ioglycoside 3b by m eth yl triflate-

prom oted con den zation with pen t-4-en -1-ol in dich lorom eth an e. Eth yl

th ioglycoside 8, pen t-4-en yl glycosides 10a an d 10b an d 4-O-trim eth ylsilyl

derivative 11 were ch osen as glycosyl acceptors for th is com parative study.

Com poun d 11 represen ts glycosyl acceptor suited for glycosylation with

glycosyl fluorides an d silicon -based catalysis²⁶. Com poun ds 8, 10a an d 10b

were prepared by Zem plén deacetylation from 4-O-acetates 3a, 9a an d 9b

respectively. Silyl derivative 11 was obtain ed by reaction of com poun d 10a

with trim eth ylsilyl ch loride an d h exam eth yldisilazan e in a m ixture of

dich orom eth an e an d pyridin e.

Th e results of th e presen ted com parative in vestigation of th e m ost widely

used glycosylation m eth ods usin g above specified glycosyl don ors 3a, 4, 5b

an d 7, an d glycosyl acceptors 8, 10a, 10b an d 11 in th e syn th esis of m odel

disacch arides con tain in g (1→4)-lin ked 2-am in o-2-deoxygalactopyran ose

un its are sum m arized in Table I. Th e silver triflate prom oted glycosylation

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1918

Veselý, Ledvina, Jindřich, Trnka, Šaman:

OBn

AcO

RO

OBn

AcO

BnO

g

O

OPent

Br

NPht

4

9a, R = Bn

9b, R = All

a

e

f

OBn

HO

RO

O

OBn

AcO

BnO

OBn

OPent

AcO

RO

O

b

c

NPht

O

X

SEt

10a, R = Bn

10b, R = All

NPht

Y

NPht

5a, X = H, Y = F

5b, X = F, Y = H

h

3a, R=Bn

3b, R=All

OBn

O

OBn

TMSO

BnO

AcO

O

OPent

OH

BnO

NPht

11

NPht

d

6

OBn

HO

RO

OBn

AcO

BnO

O

NH

CCl₃

O

e

SEt

O

NPht

8, R=Bn

7

a) Br₂, CH₂Cl₂; b) NBS, DAST in CH₂Cl_2,-35 °C; c) NIS, H₂O and acetone; d) CCl₃CN and

DBU in toluene, 0°C and then r.t.; e) MeONa in MeOH; f) pent-4-en-1-ol and MeOTf in CH₂Cl₂;

g) pent-4-en-1-ol and AgClO₄in CH₂Cl₂; h) TMSCl and HMDS in CH₂Cl₂and pyridine

SCHEME 2

of ethyl thioglycoside 8 with glycosyl brom ide 4 in dichlorom ethane at –45 °C

in th e presen ce of base gave th e expected disacch aride 12 in a very low

yield an d eth yl th ioglycoside 3a was obtain ed as a m ajor product (Sch em e 3).

Th e base, in th e case of little reactive glycosyl acceptors acts as a glyco-

OBn

AcO

SEt

NPht

O

a or b

OBn

O

+

3a

4

8

+

BnO

NPht

BnO

12

a) AgOTf, CH₂Cl₂, -45°C; b) AgClO₄, AgCO₃, CH₂Cl₂, r.t.

SCHEME 3

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1919

sylation in h ibitor^27,28. Application of th e glycosidation procedure usin g sil-

ver perch lorate in th e presen ce of silver carbon ate⁹, wh ich acts as a scaven -

ger of h ydrogen brom ide, did n ot lead to sign ifican t in crease in th e produc-

tion of target com poun d 12 an d eth yl glycoside 3a was still a m ajor prod-

uct. Th e form ation of un expected eth yl th ioglycoside 3a can be in terpreted

as a result of low reactivity of axially orien ted OH(4) group of glycosyl ac-

ceptor (Sch em e 4). Due to th is fact th e activated form of glycosyl don or at-

tacks m ain ly sulfur at th e reducin g en d of glycosyl acceptor to give sulfon -

ium ion A. Th e ion decom poses to form eth yl th ioglycoside 3a an d carbo-

cation B, wh ich is stabilized by elim in ation to form glycal C. An an alogous

OBn

HO

AcO

BnO

O

+

glycosyl

promotor

SEt

BnO

Br

+

NPht

4

8

OBn

BnO

OBn

AcO

BnO

OH

HO

BnO

Et

O

OBn

SEt

S

BnO

NPht

3a

B

A

-H⁺

OBn

HO

BnO

O

C

NPht

SCHEME 4

couplin g of th e correspon din g syn th on s with gluco con figuration followed

the expected course, to afford disaccharide 14 in a very good yield (Schem e 5).

Th e problem of in term olecular m igration of eth ylsulfan yl group was solved

by usin g glycosyl acceptor h avin g pen t-4-en yl group at th e reducin g en d.

BnO

AcO

OBn

BnO

O

a

AcO

BnO

HO

BnO

+

Br

O

BnO

SEt

BnO

NPht

13

1a

14

a) AgOTf, CH₂Cl₂, -45 °C

SCHEME 5

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1920

Veselý, Ledvina, Jindřich, Trnka, Šaman:

Couplin g of glycosyl brom ide 4 with pen t-4-en yl glycoside 10a (Sch em e 6)

prom oted with silver perch lorate in th e presen ce of silver carbon ate gave a

m ixture of β(1→4)- an d α(1→4)-lin ked disacch arides 16a an d 16b, respec-

tively, in th e 2.7:1 ratio, in a total yield of 78%. Th e use of eth yl th io-

glycoside 3a as glycosyl don or activated with m eth yl triflate, by usin g th e

procedure as reported in th e literature²⁰, led to an in crease in th e yield of

α(1→4)-lin ked disacch aride 16b, but th e overall yield was low. Th e attem pt

R³O

R²O

OBn

AcO

R¹O

O

+

OPent

Y

NPht

3a, R¹= Bn, X = SEt

4, R¹= Bn, X = Br

5b, R¹= Bn, X = F

10a, R²= Bn, R³= H

10b, R²= All, R³= H

11, R²= Bn, R³= TMS

7, R¹= Bn, X = OC(NH)CCl₃

OBn

AcO

O

OBn

AcO

R¹O

OPent

NPht

OPent

O

OBn

PhtN

O

OBn

R²O

O

+

R¹O

O

NPht

R²O

16b, R¹= R²= Bn

17b, R¹= Bn, R²= All

16a, R¹= R²= Bn

17a, R¹= Bn, R²=All

SCHEME 6

to couple β-glycosyl fluoride 5b with pen ten yl glycoside 10a by usin g tita-

n ium tetrafluoride as glycosyl prom otor²⁹afforded, beside un reacted start-

in g com poun ds, 24% of disacch aride 16a, 17% of disacch aride 16b an d

15% of α-glycosyl fluoride 5a. Th e sam e couplin g carried out with th e use

of m etallocen e (Cp₂ZrCl₂/AgClO₄) as a catalyst^30,31gave, in addition to

un reacted startin g com poun ds, 36% of disacch aride 16a an d 14% of

disacch aride 16b. Glycosylation usin g glycosyl fluorides as glycosyl don ors

an d silicon -based catalysis²⁶, wh ich em ploys th e em in en t affin ity of silicon

to fluorin e, was un successful. Th e trim eth ylsilyl triflate prom oted reaction

of 5b with 10a yielded a com plex m ixture from wh ich th e target

disacch aride 16a was isolated in a very low yield. Couplin g of glycosyl

trich loroacetim idate 7 with 10a prom oted with boron trifluoride eth erate⁷

afforded, in addition to un reacted glycosyl acceptor 10a, 30% of

disacch aride 16a an d 11% of disacch aride 16b. A sign ifican t in crease in

stereoselectivity an d efficien cy of th is glycosylation , i.e., form ation of

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1921

β(1→4)- an d α(1→4)-lin ked disacch arides 16a an d 16b in th e ratio 5:1 an d

60% overall yield, was ach ieved by usin g trim eth ylsilyl triflate as a stron ger

Lewis acid. Th e replacem en t of ben zyl protectin g group in position OH(4)

with less bulky allyl group did n ot h ave an y positive effect. Silver perch lo-

rate in th e presen ce of silver carbon ate prom oted couplin g of glycosyl bro-

m ide 4 with pen ten yl glycoside 10b gave, in addition to un reacted glycosyl

acceptor 10b, 17% of disacch aride 17a an d 11% of disacch aride 17b.

Sum m arizin g th e results (Table I) revealed th at th e stereoselectivity

an d efficien cy of glycosylation of D-galactosam in e in com parison with D-

glucosam in e was lower, due to th e low reactivity of axially orien ted OH(4)

group in a galactopyran ose rin g. Th e m axim um overall yields of β(1→4)-

an d α(1→4)-lin ked disacch arides were obtain ed by silver perch lorate in th e

presen ce silver carbon ate prom oted glycosylation with glycosyl brom ide.

Quite a good stereoselectivity in favor of β(1→4)-lin ked disacch arides was

ach ieved by Sch m idt’s trich loroacetim idate m eth od.

EXPERIMENTAL

Meltin g poin ts were determ in ed on a Kofler block an d are un corrected. Specific rotation s

were m easured on a Perkin –Elm er 141 polarim eter at 22 °C an d are given in deg cm ²g^–1

.

Elem en tal an alyses were perform ed usin g a Perkin –Elm er 2400 II in strum en t. NMR spectra

were recorded on a Bruker Avan ce 500 spectrom eter in th e FT m ode at 500.1 MHz (¹H) an d

at 125.8 MHz (¹³C) in CDCl₃or (CD₃)₂SO, usin g tetram eth ylsilan e as in tern al stan dard for

¹H NMR spectra an d CDCl₃(δ 77.0) or (CD₃)₂SO (δ 39.7) sign als as stan dards for ¹³C NMR

spectra. For un am biguous assign m en t of sign als in ¹³C NMR spectra, ¹H- an d ¹³C-h etero-

correlated 2D NMR spectra were m easured by gHSQC an d gHMBC tech n iques usin g th e

stan dard pulse sequen ces delivered by th e producer of th e spectrom eter. Th e followin g typi-

cal param eters were used: spectral width in both f₁an d f₂dim en sion s 5000 an d 17 000 Hz,

respectively, n um ber of scan s 16, n um ber of in crem en ts in f₁dim en sion 256, recycle delay

1 s, acquisition tim e 0.2 s, 90° pulse for ¹H was 12.5 µs, data m atrix for processin g 2048 ×

2048 datapoin ts. For processin g, sh ifted sin ebell weigh tin g fun ction was used. Ch em ical

sh ifts are given in ppm (δ-scale) an d couplin g con stan ts (J) in Hz. Positive-ion FAB m ass

spectra were m easured on a BeqG-geom etry m ass spectrom eter ZAB-EQ (VG An alytical,

Man ch ester, U.K.) usin g an M-Scan FAB gun (Xe, en ergy 8 keV) at an acceleratin g voltage of

8 kV. Sam ples were dissolved in ch loroform or m eth an ol, an d a m ixture of glycerol an d

th ioglycerol or dim eth yl sulfoxide was used as m atrix. Th in -layer ch rom atograph y (TLC) was

perform ed on DC-Alufolien Kieselgel 60 F₂₅₄(Merck, Darm stadt, Germ an y) or Silufol UV₂₅₄

(Kavalier, Votice, Czech Republic) silica gel sh eets. Preparative ch rom atograph y was per-

form ed on a silica gel colum n , particle size 40–60 µm (Fluka, Neu-Ulm , Switzerlan d). An alyt-

ical RP HPLC was perform ed usin g a Waters in strum en t (PDA detector, software Milen n ium

32; Milford, MA, U.S.A.) equipped with a Nova-Pak C18 colum n (150 × 3.9 m m ), particle

size 4 µm . Preparative RP HPLC was perform ed on a colum n (250 × 25 m m ) filled with

LiCh rosorb RP-18, particle size 5 µm (Merck, Darm stadt, Germ an y). Solven ts were evapo-

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1922

Veselý, Ledvina, Jindřich, Trnka, Šaman:

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1923

rated on a rotary vacuum evaporator at 40 °C. An alytical sam ples were dried at 6.5 Pa an d

25 °C for 8 h .

Eth yl 3,6-Di-O-ben zyl-2-deoxy-4-O-m esyl-2-ph th alim ido-1-th io-β-D-

glucopyran oside (2a) an d Eth yl 3-O-Allyl-6-O-ben zyl-2-deoxy-4-O-m esyl-

2-ph th alim ido-1-th io-β-D-glucopyran oside (2b)

Eth yl 3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside^19–21(1a; 53.4 g,

100 m m ol) or eth yl 3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran os-

ide^18,20(1b; 48.4 g, 100 m m ol) was dried at room tem perature an d 20 Pa for 6 h an d th en

dissolved in pyridin e (600 m l). Mesyl ch loride (50 m l, 646 m m ol) was slowly added un der

stirrin g an d th e m ixture was stirred at room tem perature for 24 h . Progress of th e reaction

was m on itored by TLC in toluen e–eth yl acetate (5:1). Toluen e (3000 m l) was added an d th e

m ixture was wash ed with cool 1 M aqueous HCl (3 × 800 m l), water (3 × 600 m l), dried over

an h ydrous m agn esium sulfate an d evaporated in vacuo.

Compound 2a: Yield 58.7 g (96%) of a solid 2a, ch rom atograph ically h om ogen ous in th e

solven t system m en tion ed above. An an alytical sam ple was prepared by crystallization from

toluen e–petroleum eth er; m .p. 60–62 °C, [α]_D+76 (c 0.9, ch loroform ). ¹H NMR: see Table II,

¹³C NMR: see Table V. For C₃₁H₃₃NO₈S₂calculated: relative m olecular m ass 611.7,

m on oisotopic m ass 611.2. ESI MS, m/z: 634.0 [M + Na]⁺. For C₃₁H₃₃NO₈S₂(611.7) calculated:

60.87% C, 5.44% H, 2.29% N, 10.48% S; foun d: 60.96% C, 5.56% H, 2.21% N, 10.31% S.

Compound 2b: Yield 53.9 g (96%) of a syrupy com poun d 2b, ch rom atograph ically h om og-

en ous in th e solven t system m en tion ed above. An an alytical sam ple was prepared by ch ro-

m atograph y on a silica gel colum n in toluen e–eth yl acetate (9:1), syrup; [α]_D+44 (c 0.5,

ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see Table V. For C₂₇H₃₁NO₈S₂calculated: rela-

tive m olecular m ass 561.7, m on oisotopic m ass 561.2. ESI MS, m/z: 584.1 [M + Na]⁺, 600.1

[M + K]⁺. For C₂₇H₃₁NO₈S₂(561.7) calculated: 57.74% C, 5.56% H, 2.49% N, 11.42% S;

foun d: 57.98% C, 5.71% H, 2.58% N, 11.14% S.

Eth yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-

galactopyran oside (3a) an d Eth yl 4-O-Acetyl-3-O-allyl-6-O-ben zyl-

2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (3b)

Com poun d 2a (15.3 g, 25 m m ol) or com poun d 2b (14.0 g, 25 m m ol) an d fresh ly m elted so-

dium acetate (131 g, 1600 m m ol) were dried in a flask equipped with a reflux con den ser at

room tem perature an d 20 Pa for 4 h an d th en th e apparatus was flush ed with argon (2×).

Dry dim eth yl sulfoxide (1400 m l) was added an d th e reaction m ixture was stirred un der

argon atm osph ere at 130 °C for 24 h . Progress of th e reaction was m on itored on TLC in

toluen e–eth yl acetate (5:1). Th e solven t was evaporated in vacuo at 90 °C an d th e residue

was partition ed between toluen e (1000 m l) an d water (700 m l). Organ ic layer was separated,

wash ed with water (2 × 700 m l), dried over an h ydrous m agn esium sulfate an d evaporated.

Th e residue was ch rom atograph ed on a silica gel colum n (350 g) in toluen e–eth yl acetate (7:1).

Compound 3a: Yield 10.4 g (72%) of a syrupy com poun d 3a; [α]_D+65 (c 0.6, ch loroform ),

lit.¹⁶gives [α]_D+64 (c 1.0, ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see Table V. For

C

₃₂H₃₃NO₇S calculated: relative m olecular m ass 575.7, m on oisotopic m ass 575.2. FAB MS,

m/z: 514 [M – EtSH + H]⁺. ESI MS, m/z: 598.3 [M + Na]⁺, 614.1 [M + K]⁺. For C₃₂H₃₃NO₇S

(575.7) calculated: 66.76% C, 5.78% H, 2.43% N, 5.57% S; foun d: 67.04% C, 5.89% H,

2.53% N, 5.49% S.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1924

Veselý, Ledvina, Jindřich, Trnka, Šaman:

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1925

Compound 3b: Yield 8.5 g (65%) of a syrupy com poun d 3b; [α]_D+33 (c 0.3, ch loroform );

lit.¹⁸gives [α]_D+24 (c 0.6, ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see Table V. For

C

₂₈H₃₁NO₇S calculated: relative m olecular m ass 525.6, m on oisotopic m ass 525.2. FAB MS,

m/z: 526 [M + H]⁺, 548 [M + Na]⁺. For C₂₈H₃₁NO₇S (525.6) calculated: 63.98% C, 5.94% H,

2.66% N, 6.10% S; foun d: 64.17% C, 6.07% H, 2.72% N, 6.21% S.

4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-α/β-D-galactopyran osyl Brom ide (4)

Com poun d 3a (576 m g, 1 m m ol) was dried in an apparatus equipped with a septum by

co-distillation with dry ben zen e (3 × 10 m l) an d th en at room tem perature an d 20 Pa for

4 h . Th e apparatus was flush ed with argon (2×) an d dry dich lorom eth an e (2 m l) was added

th rough th e septum . After dissolution , th e m ixture was cooled to 0 °C an d 1 M solution of

brom in e in dry dich lorom eth an e (1.1 m l, 1.1 m m ol) was added th rough th e septum . Th e

m ixture was stirred at 0 °C for 1 h . In th e sam e apparatus th e solven ts were evaporated in

vacuo (water pum p) with exclusion of m oisture. Th e residue was co-evaporated with toluen e

(3 × 10 m l) at 20 Pa, an d lyoph ilized from ben zen e. Yield 590 m g (98%) of α/β-an om eric

m ixture (3:4) of com poun d 4; [α]_D+77 (c 0.1, ch loroform ). Th e ratio of an om ers was deter-

m in ed by ¹H NMR spectra. ¹H NMR: see Table II, ¹³C NMR: see Table V. For C₃₀H₂₈BrNO₇

calculated: relative m olecular m ass 594.5, m on oisotopic m ass 593.1. FAB MS, m/z: 594 [M +

H]⁺. For C₃₀H₂₈BrNO₇(594.5) calculated: 60.61% C, 4.75% H, 13.44% Br, 2.36% N; foun d:

66.89% C, 4.91% H, 13.32% Br, 2.38% N.

4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-α-D-galactopyran osyl Fluoride (5a) an d

4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran osyl Fluoride (5b)

Com poun d 3a (1.73 g, 3.0 m m ol) was dried at room tem perature an d 20 Pa for 4 h , th en

N-brom osuccin im ide (1.07 g, 6.0 m m ol) was added an d dryin g was con tin ued in an appara-

tus equipped with a septum for an oth er 1 h . Th e apparatus was flush ed with argon (2×) an d

dry dich lorom eth an e (70 m l) was added trough th e septum . After dissolution , th e m ixture

was cooled to –45 °C an d (dieth ylam in o)sulfur trifluoride (DAST) (1 m l, 5.1 m m ol) was

added un der stirrin g th rough th e septum an d th e stirrin g was con tin ued at –35 °C for 6 h .

Saturated aqueous sodium h ydrogen carbon ate (30 m l) was added an d th e m ixture was

stirred at room tem perature for an oth er 1 h . Th e organ ic layer was separated, wash ed with

water (3 × 15 m l), dried over an h ydrous m agn esium sulfate an d evaporated in vacuo. Ch ro-

m atograph y of th e residue on silica gel colum n (80 g) in toluen e–eth yl acetate (20:1) af-

forded 72 m g (5%) of α-an om er 5a an d 1.1 g (69%) of β-an om er 5b.

Compound 5a: Syrup; [α]_D+96 (c 0.2, ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see

Table V. For C₃₀H₂₈FNO₇calculated: relative m olecular m ass 533.5, m on oisotopic m ass

533.2. ESI MS, m/z: 514 [M – F]⁺, 556 [M + Na]⁺. For C₃₀H₂₈FNO₇(533.5) calculated: 67.53% C,

5.29% H, 3.56% F, 2.63% N; foun d: 67.26% C, 5.55% H, 3.36% F, 2.48% N.

Compound 5b: Solid; [α]_D+65 (c 0.1, ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see

Table V. For C₃₀H₂₈FNO₇calculated: relative m olecular m ass 533.5, m on oisotopic m ass

533.2. ESI MS, m/z: 514 [M – F]⁺, 556 [M + Na]⁺. For C₃₀H₂₈FNO₇(533.5) calculated: 67.53% C,

5.29% H, 3.56% F, 2.63% N; foun d: 67.48% C, 5.43% H, 3.39% F, 2.54% N.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1926

Veselý, Ledvina, Jindřich, Trnka, Šaman:

4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran ose (6)

Com poun d 3a (1.04 g, 1.8 m m ol) an d N-iodosuccin im ide (930 m g, 4.1 m m ol) were dis-

solved un der stirrin g in a m ixture aceton e–water (4:1, 30 m l) at room tem perature an d stir-

rin g was con tin ued for 12 h . Th e solven ts were evaporated in vacuo an d th e residue was

co-distilled with toluen e (3 × 30 m l) an d th en dissolved in ch loroform (30 m l). Th e solution

was wash ed with 30% aqueous sodium th iosulfate (3 m l), water (2 × 3 m l), dried over an h y-

drous m agn esium sulfate an d evaporated in vacuo, givin g 950 m g (98%) of com poun d 6;

[α]_D+66 (c 0.3, ch loroform ). Com poun d 6 with out specification of con figuration on th e

an om eric cen tre is described in th e literature²⁵as a product of deallylation product of ap-

propriate allyl glycoside; [α]_D+83 (c 0.6, ch loroform ). ¹H NMR: see Table II, ¹³C NMR: see

Table V. For C₃₀H₂₉NO₈calculated: relative m olecular m ass 531.5, m on oisotopic m ass 531.5.

FAB MS, m/z: 514 [M – H₂O]⁺, 554 [M + Na]⁺. For C₃₀H₂₉NO₈(531.5) calculated: 67.79% C,

5.50% H, 2.64% N; foun d: 67.61% C, 5.61% H, 2.49% N.

O-(4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran osyl)

Trich loroacetim idate (7)

Com poun d 6 (870 m g, 1.6 m m ol) was dried in an apparatus equipped with a septum at

room tem perature an d 20 Pa for 4 h . Th e apparatus was flush ed with argon (2×) an d dry

toluen e (23 m l) was added th rough th e septum . After dissolution , th e m ixture was cooled to

0 °C, an d trich loroaceton itrile (2 m l, 9.6 m m ol) an d 1 M solution of DBU in toluen e (320 µl,

0.32 m m ol) were added th rough th e septum . Th e stirrin g was th en con tin ued at room tem -

perature for 24 h . Progress of th e reaction was m on itored on TLC in toluen e–eth yl acetate

(1:1). A saturated aqueous am m on ium ch loride (2 m l) was added. Organ ic layer was sepa-

rated, wash ed with water (2 × 10 m l), th en dried over an h ydrous m agn esium sulfate an d

evaporated in vacuo. Ch rom atograph y of th e residue on a silica gel colum n (20 g) in

toluen e–eth yl acetate (20:1) afforded 680 m g (63%) of com poun d 7; [α]_D+63 (c 0.2, ch loro-

form ). Com poun d 7 is described in ²⁵as in com plete ch aracterized in term ediate. ¹H NMR: see

Table II, ¹³C NMR: see Table V. For C₃₂H₂₉Cl₃N₂O₈calculated: relative m olecular m ass

675.9, m on oisotopic m ass 674.1. FAB MS, m/z: 514 [M – CCl₃CNHO]⁺, 697 [M + H]⁺. For

C

₃₂H₂₉Cl₃N₂O₈(675.9) calculated: 56.86% C, 4.32% H, 15.73% Cl, 4.14% N; foun d: 56.73% C,

4.45% H, 15.60% Cl, 4.08% N.

Eth yl 3,6-Di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (8)

Com poun d 3a (576 m g, 1 m m ol) was dried in an apparatus equipped with a septum by

co-distillation with dry ben zen e (3 × 5 m l) an d th en at room tem perature an d 20 Pa for 4 h .

Th e apparatus was flush ed with argon (2×), dry m eth an ol (10 m l) an d 1 M MeONa (100 µl,

0.1 m m ol) were added th rough th e septum an d th en th e m ixture was stirred at room tem -

perature for 80 h . Progress of th e reaction was m on itored by TLC in toluen e–eth yl acetate

(5:1). Th e m ixture was n eutralized by addition of Dowex 50 (pyridin ium form ). Th e ion

exch an ger was filtered off, wash ed with m eth an ol (20 m l) an d th e filtrate was evaporated in

vacuo. Ch rom atograph y of th e residue on a silica gel colum n (40 g) in th e above m en tion ed

solven t system gave 460 m g (80%) of a syrupy com poun d 8, wh ich was crystallized from

eth an ol to afford 444 m g (77%) of com poun d 8; m .p. 112–113 °C, [α]_D+ 58 (c 0.9, ch loro-

form ). ¹H NMR: see Table II, ¹³C NMR: see Table V. For C₂₈H₃₁NO₇S calculated: relative m o-

lecular m ass 533.6, m on oisotopic m ass 533.2. FAB MS, m/z: 472 [M – EtSH + H]⁺, 556 [M +

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1927

Na]⁺. For C₃₀H₃₁NO₆S (533.6) calculated: 67.53% C, 5.85% H, 2.63% N, 6.00% S; foun d:

67.61% C, 5.88% H, 2.61% N, 5.97% S.

Pen t-4-en yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-

galactopyran oside (9a)

A m ixture of silver perch lorate (1.4 g, 6.7 m m ol) an d m olecular sieves 3 Å (3 g) was dried in

an apparatus equipped with a septum at room tem perature an d 20 Pa for 4 h . Th e apparatus

was flush ed with argon (2×) an d dry dich lorom eth an e (30 m l) an d pen t-4-en -1-ol (2 m l,

19.4 m m ol) were added th rough th e septum an d th e m ixture was stirred at room tem pera-

ture for 1 h . Th e m ixture was cooled to –40 °C an d a solution of glycosyl brom ide 4, fresh ly

prepared from 3a (2.4 g, 4 m m ol) an d dry dich lorom eth an e (20 m l), was added th rough th e

septum un der stirrin g durin g 10 m in an d stirrin g was con tin ued at –20 °C for 12 h . A satu-

rated aqueous sodium h ydrogen carbon ate (10 m l) was added at –20 °C an d after warm in g to

room tem perature th e m ixture was diluted with dich lorom eth an e (70 m l) an d filtered

th rough a Celite. Th e filtrate was wash ed with saturated aqueous sodium h ydrogen carbon ate

(30 m l), water (3 × 30 m l), dried over an h ydrous m agn esium sulfate an d evaporated in

vacuo. Ch rom atograph y of th e residue on silica gel colum n (140 g) in toluen e–eth yl acetate

(25:1) gave 2.2 g (90%) of a syrupy com poun d 9a; [α]_D+39 (c 0.2, ch loroform ). ¹H NMR: see

Table III, ¹³C NMR: see Table V. For C₃₅H₃₇NO₈calculated: relative m olecular m ass 599.7,

m on oisotopic m ass 599.3. FAB MS, m/z: 600.8 [M + H]⁺, 622.8 [M + Na]⁺. For C₃₅H₃₇NO₈

(599.7) calculated: 70.10% C, 6.22% H, 2.34% N; foun d: 70.26% C, 6.34% H, 2.26% N.

Pen t-4-en yl 4-O-Acetyl-3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-

galactopyran oside (9b)

Com poun d 3b (1.0 g, 2.0 m m ol) was dried in an apparatus equipped with a septum by co-

distillation with dry ben zen e (3 × 15 m l) an d th en at room tem perature an d 20 Pa for 6 h .

Th e apparatus was flush ed with argon (2×) an d dry dich lorom eth an e (40 m l) was added

th rough th e septum . After dissolution , th e m ixture was cooled to –30 °C an d m eth yl triflate

(0.9 m l, 8.0 m m ol) was added un der stirrin g th rough th e septum . Th e tem perature was al-

lowed to in crease to 0 °C (durin g 15 m in ) an d pen t-4-en -1-ol (2 m l, 19.4 m m ol) was added

th rough th e septum an d stirrin g was th en con tin ued at room tem perature for 6 h . Progress

of th e reaction was m on itored by TLC in toluen e–eth yl acetate (5:1). Pyridin e (2 m l) was

added an d after 1 h stirrin g at room tem perature th e m ixture was diluted with dich loro-

m eth an e (30 m l). Th e solution was wash ed with saturated aqueous sodium h ydrogen -

carbon ate (30 m l), water (2 × 30 m l), dried over an h ydrous m agn esium sulfate an d evapo-

rated in vacuo. Ch rom atograph y of th e residue on silica gel colum n (70 g) in toluen e–eth yl

acetate (20:1) gave 1.0 g (92%) of a syrupy com poun d 9b ; [α]_D+4 (c 0.4, ch loroform ).

¹H NMR: see Table III, ¹³C NMR: see Table V. For C₃₁H₃₅NO₈calculated: relative m olecular

m ass 549.6, m on oisotopic m ass 549.2. FAB MS, m/z: 600.8 [M + H]⁺, 622.8 [M + Na]⁺. For

C

₃₁H₃₅NO₈(549.6) calculated: 67.74% C, 6.42% H, 2.55% N; foun d: 67.68% C, 6.58% H,

22.49% N.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1928

Veselý, Ledvina, Jindřich, Trnka, Šaman:

TABLE III

¹H NMR param eters of com poun ds 9–11^a

Param eter

9a

9b

10a

10b

11

δ(H-1)

5.13 d

5.15 d

5.09 d

5.12 d

5.11 d

δ(H-2)

4.39 dd

4.42 dd

4.45 dd

4.47 dd

4.57 dd

δ(H-3)

4.28 dd

4.34 dd

4.26 dd

4.28 dd

4.15 dd

δ(H-4)

5.67 dd

5.57 dd

4.16 d

4.15 bd

4.26 d

δ(H-5)

3.92 ddd

3.59 dd

3.92 ddd

3.57 dd

3.79–3.81 m

3.76–3.78 m

3.87–3.89 m

3.39 dt

3.79 dd

3.71–3.76 m

3.64 m

δ(H-6a)

δ(H-6b)

δ(H-1a′)

δ(H-1b′)

δ(H-2′)

δ(H-3′)

δ(H-4′)

δ(H-5a′)

δ(H-5b′)

3.79 dd

3.64 dd

3.63 dd

3.88 dd

3.71–3.76 m

3.36 ddd

3.79 dt

3.39 ddd

3.81 dt

3.43 ddd

3.84 dt

3.42 ddd

3.82 dt

3.80 dt

1.40–1.60 m

1.75–1.92 m

5.55 ddt

4.69 ddt

4.73 ddt

1.44–1.62 m

1.79–1.93 m

5.57 ddt

4.75 ddt

4.72 ddt

1.40–1.58 m

1.77–1.92 m

5.56 ddt

4.71 ddt

4.74 ddt

1.43–1.60 m

1.80–1.93 m

5.58 ddt

4.73 dq

1.40–1.55 m

1.74–1.87 m

5.54 ddt

4.68 ddt

4.72 ddt

4.75 ddt

J(1,2)

8.5

11.1

3.4

1.2

7.0

5.8

9.5

8.4

11.2

3.3

1.2

6.8

6.0

9.6

8.5

J(2,3)

10.9

11.0

3.3

11.1

2.8

J(3,4)

3.3

b

J(4,5)

0.0

b

J(5,6a)

J(5,6b)

J(6a,6b)

5.8

b

8.2

11.8

a

Param eters of pen t-4-en yl residue sign ed H-1′ to H-5′, typical values of couplin g con stan ts

in pen t-4-en yl residue: J_1a′,2a′= 6.3, J_1a′,2b′= 7.1, J_1b′,2a′= J_1b′,2b′= 6.2, J_1a′,1b′= 9.8, J_3a′,4′

=

J_3b′,4′= 6.6, J_3a′,5a′= J_3a′,5a′= 1.7, J_3a′,5b′= J_3b′,5b′= 1.4, J_4′,5a′= 17.0, J_4′,5b′= 10.3, J_5a′,5b′= 1.9.

Addition al NMR param eters an d param eters of substituen ts: 9a – arom . H: 6.89–7.87 m ,

OCH₂C₆H₅: 4.26 d (1 H, J = 12.4), 4.50 d (1 H, J = 11.9), 4.60 d (1 H, J = 11.9), 4.60 d (1 H,

J = 12.4), OAc: 2.14 s; 9b – arom . H: 7.28–7.89 m , OCH₂C₆H₅: 4.50 d (1 H, J = 11.9), 4.59 d

(1 H, J = 11.9), OAc: 2.14 s, OCH₂CH=CH₂: 3.80 ddt (1 H, J = 1.3, 1.3, 6.3, 12.9), 4.06 ddt

(1 H, J = 1.5, 1.5, 5.1, 12.9), 5.56 dddd (J = 5.1, 6.3, 10.4, 17.2), 4.95 ddt (J = 1.3, 1.3, 1.7,

10.4), 5.05 dq (J = 3 × 1.6, 17.2); 10a – arom . H: 6.96–7.92 m , OCH₂C₆H₅: 4.34 d (1 H, J =

12.3), 4.64 d (1 H, J = 12.3), 4.62 s (2 H); 10b – arom . H: 7.26–7.92 m , OCH₂C₆H₅: 4.62 s

(2 H), OCH₂CH=CH₂: 3.88 ddt (1 H, J = 1.4, 1.4, 5.9, 12.9), 4.07 ddt (1 H, J = 1.4, 1.4, 5.5,

12.9), 5.65 ddt (1 H, J = 5.8, 5.8, 10.4, 17.2), 4.99 dq (1 H, J = 3 × 1.3, 10.4), 5.11 dq (1 H,

J = 3 × 1.5, 17.2); 11 – arom . H: 6.92–7.83 m , OCH₂C₆H₅: 4.23 d (1 H, J = 12.1), 4.56 d (1 H,

b

J = 11.9), 4.59 d (1 H, J = 11.9), 4.64 d (1 H, J = 12.1), OSi(CH₃)₃: 0.15 s (9 H). Value n ot

determ in ed.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1929

Pen t-4-en yl 3,6-Di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (10a) an d

Pen t-4-en yl 3-O-Allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (10b)

Com poun d 9a (1.2 g, 2.0 m m ol) or com poun d 9b (1.1 g, 2 m m ol) was dried in an apparatus

equipped with a septum by co-distillation with dry ben zen e (3 × 10 m l) an d th en at room

tem perature an d 20 Pa for 6 h . Th e apparatus was flush ed with argon (2×) an d dry m eth an ol

(40 m l) an d 0.5 M MeONa in m eth an ol (0.5 m l) were added th rough th e septum . Th e m ix-

ture was stirred at room tem perature for 7 days: Progress of th e reaction was m on itored on

TLC in toluen e–eth yl acetate (5:1). Th e m ixture was n eutralized by addition of Dowex 50

(pyridin ium form ), th e ion exch an ger was filtered off, wash ed with m eth an ol (50 m l) an d

filtrate was evaporated in vacuo. Th e residue was ch rom atograph ed on a silica gel colum n

(100 g) in toluen e–eth yl acetate (10:1)

Compound 10a: Yield 981 m g (88%) of a syrupy com poun d 10a; [α]_D+33 (c 0.6, ch loro-

form ). ¹H NMR: see Table III, ¹³C NMR: see Table V. For C₃₃H₃₅NO₇calculated: relative m o-

lecular m ass 557.6, m on oisotopic m ass 557.2. FAB MS, m/z: 558.2 [M + H]⁺, 580.2 [M + Na]⁺.

For C₃₃H₃₅NO₇(557.6) calculated: 71.08% C, 6.33% H, 2.51% N; foun d: 71.19% C, 6.41% H,

2.43% N.

Compound 10b: Yield 822 m g (81%) of a syrupy com poun d 10b; [α]_D+5 (c 0.4, ch loro-

form ). ¹H NMR: see Table III, ¹³C NMR: see Table V. For C₂₉H₃₃NO₇calculated: relative m o-

lecular m ass 507.6, m on oisotopic m ass 507.2. FAB MS, m/z: 508.2 [M + H]⁺, 530.7 [M + Na]⁺.

For C₂₉H₃₃NO₇(507.6) calculated: 68.62% C, 6.55% H, 2.76% N; foun d: 68.49% C, 6.68% H,

2.64% N.

Pen t-4-en yl 3,6-Di-O-ben zyl-2-deoxy-2-ph th alim ido-4-O-(trim eth ylsilyl)-β-D-

galactopyran oside (11)

Com poun d 10a (160 m g, 0.3 m m ol) was dried in an apparatus equipped with a septum by

co-distillation with dry ben zen e (3 × 5 m l) an d th en at room tem perature an d 20 Pa for 4 h .

Th e apparatus was flush ed with argon (2×), an d dry dich lorom eth an e (9 m l) an d dry pyri-

din e (4.5 m l) were added th rough th e septum . After dissolution , 1,1,1,3,3,3-h exam eth yl-

disilazan e (130 µl, 0.6 m m ol) an d ch lorotrim eth ylsilan e (150 µl, 1.2 m m ol) were added un -

der stirrin g th rough th e septum an d stirrin g was con tin ued at room tem perature for 48 h .

Progress of th e reaction was m on itored on TLC in toluen e–eth yl acetate (5:1). Th e reaction

m ixture was evaporated in vacuo an d th e residue was ch rom atograph ed on a silica gel col-

um n (12 g) in toluen e–eth yl acetate (20:1), to give 160 m g (88%) of a syrupy com poun d 11;

[α]_D+24 (c 0.02, ch loroform ). ¹H NMR: see Table III, ¹³C NMR: see Table V. For

C

₃₆H₄₃NO₇Si calculated: relative m olecular m ass 629.8, m on oisotopic m ass 629.3. ESI MS,

m/z: 652 [M + H]⁺. For C₃₆H₄₃NO₇Si (629.8) calculated: 68.65% C, 6.88% H, 2.22% N;

foun d: 68.41% C, 7.07% H, 2.11% N.

Eth yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran osyl-

(1→4)-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-galactopyran oside (12)

Method A. A m ixture of com poun d 8 (133 m g, 0.25 m m ol) an d silver trifluorom eth an e-

sulfon ate (90 m g, 0.35 m m ol) was dried in a flask equipped with a septum at room tem pera-

ture an d 20 Pa for 8 h . Th e apparatus was flush ed with argon (2×) an d dry dich lorom eth an e

(0.7 m l) was added th rough th e septum . After dissolution , th e m ixture was cooled to –45 °C,

an d a solution of glycosyl brom ide 4, fresh ly prepared from 3a (216 m g, 0.38 m m ol) an d

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1930

Veselý, Ledvina, Jindřich, Trnka, Šaman:

dry dich lorom eth an e (0.6 m l), was added un der stirrin g th rough th e septum durin g 1 h . Th e

m ixture was stirred at –45 °C for an oth er 1 h an d at –20 °C for 30 m in . Pyridin e (0.5 m l)

was added at –20 °C an d after warm in g to room tem perature th e m ixture was diluted with

ch loroform (5 m l) an d filtered. Th e filtrate was wash ed with 0.5 M HCl (3 × 2 m l), saturated

aqueous sodium h ydrogen carbon ate (3 × 2 m l) an d water (3 × 2 m l), dried over an h ydrous

m agn esium sulfate an d evaporated in vacuo. Th e residue was separated by HPLC on silica

gel C18 colum n in solven t system water–m eth an ol (lin ear gradien t 50→100%) to give 13 m g

(5%) of a syrupy com poun d 12 an d 72 m g (50%) of a syrupy com poud 3a, wh ich is iden ti-

cal in all respects ([α]_D, MS, an d NMR spectra) with th e auth en tic com poun d 3a described

above.

Method B: A m ixture of com poun d 8 (133 m g, 0.25 m m ol), silver carbon ate (276 m g,

1.0 m m ol), silver perch lorate (62 m g, 0.3 m m ol) an d m olecular sieves 4 Å (0.8 g) was dried

in an apparatus equipped with a septum at room tem perature an d 20 Pa for 8 h . Th e appara-

tus was flush ed with argon (2×) an d dry dich lorom eth an e (1.4 m l) was added th rough th e

septum . Th e m ixture was stirred at room tem perature for 1 h an d a solution of glycosyl bro-

m ide 4, fresh ly prepared from 3a (216 m g, 0.38 m m ol) an d dry dich lorom eth an e (0.6 m l),

was added un der stirrin g th rough th e septum durin g 3 h . Stirrin g was con tin ued at room

tem perature for an oth er 10 h an d th en pyridin e (1 m l) was added. Th e reaction m ixture was

worked up by th e sam e procedure as is given in m eth od A to afford 45 m g (17%) of a syrupy

com poun d 12 an d 38 m g (55%) of a syrupy com poun d 3a.

Compound 12: [α]_D+18 (c 0.1, ch loroform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI.

For C₆₀H₅₈N₂O₁₃S calculated: relative m olecular m ass 1047.2, m on oisotopic m ass 1046.4.

FAB MS, m/z: 877.4 [M – (OBn an d EtS)]⁺, 1048.4 [M + H]⁺, 1069.4 [M + Na]⁺. For

C

₆₀H₅₈N₂O₁₃S (1047.2) calculated: 68.82% C, 5.58% H, 2.68% N, 3.06% S; foun d: 69.07% C,

5.67% H, 2.74% N, 2.91% S.

Eth yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-glucopyran osyl-

(1→4)-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside (14)

Eth yl 4-O-acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside²⁰(430 m g,

0.75 m m ol) was dried in an apparatus equipped with a septum at room tem perature an d 20 Pa

for 10 h . Th e apparatus was flush ed with argon (2×) an d dry dich lorom eth an e (1.7 m l) was

added th rough th e septum . After dissolution , th e m ixture was cooled to 0 °C an d 1 M solu-

tion of brom in e in dry dich lorom eth an e (0.8 m l) was added th rough th e septum un der stir-

rin g. Th en th e m ixture was stirred at 0 °C for 1 h an d th en at room tem perature for 1 h . In

th e sam e apparatus th e solven ts were evaporated in vacuo (water pum p) with exclusion of

m oisture. Th e residue was co-evaporated with toluen e (3 × 1.5 m l) at 20 Pa, added th rough

th e septum an d th e residue was dissolved in dry dich lorom eth an e (1 m l). Th e solution of

glycosyl brom ide²⁰13 was used for th e con den zation with 1a.

A m ixture of eth yl 3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-1-th io-β-D-glucopyran oside^19,20

(1a; 266 m g, 0.5 m m ol) an d silver trifluorom eth an esulfon ate (193 m g, 0.75 m m ol) was dried

in an apparatus equipped with a septum at room tem perature an d 20 Pa for 8 h . Th e appara-

tus was wash ed with argon (2×) an d dry dich lorom eth an e (1 m l) was added th rough th e sep-

tum . After dissolution , th e m ixture was cooled to –45 °C an d a solution of glycosyl brom ide

13 was added th rough th e septum un der stirrin g durin g 1 h . Th en th e m ixture was stirred at

–45 °C for an oth er 1 h an d at –20 °C for 30 m in . Pyridin e (0.5 m l) was added at –20 °C an d

after warm in g to room tem perature th e m ixture was diluted with ch loroform (10 m l) an d

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1931

filtered. Th e filtrate was wash ed with 0.5 M HCl (3 × 3 m l), saturated aqueous sodium

h ydrogen carbon ate (3 × 3 m l), water (3 × 3 m l), dried over an h ydrous m agn esium sulfate

an d evaporated in vacuo. Ch rom atograph y of th e residue on a silica gel colum n (30 g) in

toluen e–eth yl acetate (9:1) gave 320 m g (61%) of solid com poun d 14; [α]_D+47 (c 1.3, ch lo-

roform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI. For C₆₀H₅₈N₂O₁₃S calculated: relative

m olecular m ass 1047.2, m on oisotopic m ass 1046.4. FAB MS, m/z: 877.4 [M – (OBn an d

EtS)]⁺, 1048.4 [M + H]⁺, 1069.4 [M + Na]⁺. For C₆₀H₅₈N₂O₁₃S (1047.2) calculated: 68.82% C,

5.58% H, 2.68% N; foun d: 69.09% C, 5.64% H, 2.67% N.

Pen t-4-en yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran osyl-

(1→4)-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (16a) an d

Pen t-4-en yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-α-D-galactopyran osyl-

(1→4)-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (16b)

Method A: Com poun d 10a (112 m g, 0.2 m m ol) was dried in an apparatus equipped with a

septum by co-distillation with dry ben zen e (3 × 3 m l), added th rough th e septum . Silver car-

bon ate (320 m g, 1.16 m m ol), silver perch lorate (67 m g, 0.32 m m ol) an d m olecular sieves 4 Å

(300 m g) were added an d dryin g was con tin ued at room tem perature an d 20 Pa for an oth er

TABLE IV

¹H NMR param eters of com poun ds 12–17b^a

Para-

m eter

12

14

16a

16b

16c

17a

17b

δ(H-1)

δ(H-2)

δ(H-3)

δ(H-4)

δ(H-5)

δ(H-6a)

δ(H-6b)

δ(H-1′)

δ(H-2′)

δ(H-3′)

δ(H-4′)

δ(H-5′)

δ(H-6a′)

4.94 dd

4.11 t

5.10 m

4.88 d

4.90 d

4.93 d

5.03 d

4.02 dd

4.03 dd

3.94 dd

3.64 ddd

3.75 dd

3.88 dd

5.44 d

4.05 dd

4.01 dd

3.97 dd

3.64 ddd

3.74 dd

3.89 dd

5.24 d

4.77 dd

4.08 dd

4.32 dd

3.53 dd

3.02 dd

3.14 dd

5.30 d

4.38 dd

4.15 dd

4.17 dd

3.75 ddd

3.78 dd

3.88 dd

5.81 d

4.08 ddd 4.14–4.19 m 3.98 dd

4.05 dd

3.93 dd

3.60 ddd

3.73 dd

3.90 dd

5.28 d

3.65 ddd 3.34 ddd

3.70 dd

3.84 dd

5.32 d

3.38 dd

3.52 dd

5.33

4.47 dd

4.43 dd

5.67 dd

4.27 dd

4.77 dd

5.15 dd

4.53 dd

4.40 dd

5.66 dd

3.88 ddd

3.49 dd

3.51 dd

3.25 ddd

3.67 dt

4.69 dd

5.95 dd

5.48 dd

4.08 ddd

4.04 dd

4.17 dd

3.28 ddd

3.71 dt

4.49 dd

4.38 dd

5.64 dd

3.86 dt

4.76 dd

5.61 dd

5.88 dd

4.83 ddd

3.30 dd

3.38 dd

3.29 ddd

3.50 dt

4.98 dd

5.58 t

4.45 dd

5.37 ddd

4.26 dd

4.33 dd

3.35 ddd

3.79 dd

3.87 ddd 3.66 ddd

3.49 dd

3.44 dd

δ(H-6b′) 3.51 dd

3.54 dd

3.51 d

δ(H-1a′′)

δ(H-1b′′)

δ(H-2′′)

δ(H-3′′)

δ(H-4′′)

δ(H-5a′′)

δ(H-5b′′)

–

3.29 ddd

3.69 dt

1.33–1.51 m 1.37–1.48 m 1.38–1.55 m 1.37–1.55 m

1.60–1.82 m 1.68–1.81 m 1.73–1.82 m 1.76–1.87 m 1.74–1.88 m

5.50 ddt

4.63 ddt

4.68 ddt

5.51 ddt

4.64 ddt

4.69 ddt

5.54 ddt

4.68 ddt

4.71 ddt

5.59 ddt

4.70 ddt

4.76 ddt

5.54 ddt

4.68 dq

4.71 dd

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1932

Veselý, Ledvina, Jindřich, Trnka, Šaman:

TABLE IV

(Continued)

Para-

m eter

12

14

16a

16b

16c

17a

17b

b

J(1,2)

10.3

2.6

1.0

5.5

6.1

9.6

8.1

11.0

3.2

1.1

6.0

7.0

9.2

7.9

11.0

3.4

8.1

10.1

2.8

7.8

11.1

2.4

8.5

11.1

2.9

0.0

8.6

6.1

9.0

3.3

9.8

3.1

0.9

5.6

7.5

9.1

8.6

10.8

2.9

1.3

6.0

5.9

9.8

4.7

7.5

7.9

3.7

7.1

4.5

11.8

J(2,3)

J(3,4)

J(4,5)

9.3

1.0

0.0

1.0

J(5,6a)

J(5,6b)

J(6a,6b)

J(1′,2′)

J(2′,3′)

J(3′,4′)

J(4′,5′)

J(5′,6a′)

J(5′,6b′)

J(6a′,6b′)

4.0

1.3

5.9

6.0

6.1

5.7

5.4

5.5

11.1

8.4

10.1

8.4

10.3

8.4

10.3

8.4

10.8

9.0

11.1

3.4

11.6

3.4

11.0

3.4

9.8

0.9

0.0

0.7

2.5

6.1

6.0

6.5

4.4

7.0

6.4

6.5

b

9.9

9.2

9.8

a

Param eters of pen t-4-en yl residue sign ed H-1′′ to H-5′′, typical values of couplin g con stan ts in

pen t-4-en yl residue: J_{1a′′,2a′′}= 6.1, J_{1a′′,2b′′}= 7.3, J_{1b′′,2a′′}= J_{1b′′,2b′′}= 6.1, J_{1a′′,1b′′}= 9.7, J_{3a′′,4′′}= J_{3b′′,4′′}= 6.7,

J_{3a′′,5a′′}= J_{3a′′,5a′′}= 1.7, J_{3a′′,5b′′}= J_{3b′′,5b′′}= 1.2, J_{4′′,5a′′}= 17.1, J_{4′′,5b′′}= 10.2, J_{5a′′,5b′′}= 2.1. Addition al NMR pa-

ram eters an d param eters of substituen ts: 12 – J_1,3= 1.3, arom . H: 6.56–8.10 m , OCH₂C₆H₅: 4.25 d (1 H, J

= 12.5), 4.34 d (1 H, J = 12.7), 4.40 d (1 H, J = 11.8), 4.49 d (1 H, J = 11.8), 4.52 d (1 H, J = 12.7), 4.54 s (2

H), 4.60 d (1 H, J = 12.5), SCH₂CH₃: 2.45 dq (1 H, J = 3 × 7.4, 12.3), 2.60 dq (1 H, J = 3 × 7.4, 12.3), 1.32 t

(3 H, J = 7.3), OAc: 2.17 s (3 H); 14 – arom . H: 6.80–7.88 m , OCH₂C₆H₅: 4.32 d (1 H, J = 12.1), 4.43 d (1

H, J = 11.8), 4.44 d (1 H, J = 11.9), 4.50 d (1 H, J = 12.3), 4.52 d (1 H, J = 11.8), 4.52 d (1 H, J = 11.9),

4.60 d (1 H, J = 12.1), 4.84 d (1 H, J = 12.3), SCH₂CH₃: 2.49 dq (1 H, J = 3 × 7.5, 12.5), 2.57 dq (1 H, J = 3

× 7.5, 12.5), 1.09 t (3 H, J = 7.5), OAc: 1.92 s (3 H); 16a – arom . H: 6.52–7.80 m , OCH₂C₆H₅: 3.93 d (1 H,

J = 12.8), 4.13 d (1 H, J = 12.8), 4.27 d (1 H, J = 12.0), 4.42 d (1 H, J = 11.8), 4.50 d (1 H, J = 11.8), 4.54 d

(1 H, J = 11.9), 4.57 d (1 H, J = 11.9), 4.60 d (1 H, J = 12.0), OAc: 1.92 s (3 H); 16b – arom . H: 6.63–7.75

m , OCH₂C₆H₅: 4.02 d (1 H, J = 12.7), 4.36 d (1 H, J = 12.7), 4.59 s (2 H), OAc: 1.87 s (3 H), 2.03 s (3 H),

2.20 s (3 H); 16c – arom . H: 6.85–7.75 m , OCH₂C₆H₅: 4.25 d (1 H, J = 12.5), 4.42 d (1 H, J = 11.8), 4.50 d

(1 H, J = 11.8), 4.55 d (1 H, J = 11.9), 4.57 d (1 H, J = 11.9), 4.58 d (1 H, J = 12.5), OAc: 2.15 s (3 H),

OCH₂CH=CH₂: 3.47 ddt (1 H, J = 1.2, 1.2, 6.2, 12.8), 3.71 ddt (1 H, J = 1.4, 1.4, 5.8, 12.8), 5.30 ddt (1 H, J

= 6.0, 6.0, 10.3, 17.2), 4.75 dq (1 H, J = 3 × 1.5, 10.3), 4.80 dq (1 H, J = 3 × 1.6, 17.2); 17a – arom . H:

6.88–7.87 m , OCH₂C₆H₅: 4.15 d (1 H, J = 11.8), 4.16 d (1 H, J = 11.9), 4.18 d (1 H, J = 11.7), 4.32 d (1 H, J

= 11.9), 4.40 d (1 H, J = 11.8), 4.59 d (1 H, J = 9.5), 4.71 d (1 H, J = 11.7), 4.87 d (1 H, J = 9.5), OAc: 2.06

s (3 H); 17b – arom . H: 6.56–7.82 m , OCH₂C₆H₅: 4.06 d (1 H, J = 12.3), 4.34 d (1 H, J = 12.3), 4.61 d (1 H,

b

J = 11.8), 4.67 d (1 H, J = 11.8 ), OAc: 2.03 s (3 H), 2.06 s (3 H), 2.16 s (3 H). Value n ot determ in ed.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1933

TABLE V

¹³C NMR ch em ical sh ifts of com poun ds 2a–11^a

Com poun d

C-1

C-2

C-3

C-4

C-5

C-6

2a

81.23

81.54

81.76

90.40

78.70

106.34

104.96

93.29

94.36

81.02

98.60

98.77

98.37

98.51

98.78

54.88

54.92

51.64

51.70

54.66

56.13

51.71

52.95

54.69

51.86

51.01

53.02

53.06

52.44

52.51

52.45

78.82

78.68

73.58

74.03

71.39

72.92

69.90

72.25

72.81

72.80

75.63

73.05

73.37

75.06

79.12

77.88^b

66.05

66.28

65.52

65.64

66.05

65.30

65.90

65.62

65.74

66.00

66.19

65.63

65.84

67.55

77.85

77.91^b

76.09

76.20

72.84

77.30

70.71

72.52

72.54

73.33

77.15

72.33

72.44

73.39

73.45

73.87

68.92

68.90

68.01

68.13

67.30

67.47

67.76

67.56

68.11

67.33

69.16

68.04

68.17

69.12

69.19

68.80

2b

3a

3b

4 α-an om er

4 β-an om er

5a

5b

6

7

8

9a

9b

10a

10b

11

75.23

c

a

¹³C ch em ical sh ifts of arom atic carbon s from protectin g groups are n ot given . Addition al

¹³C NMR ch em ical sh ifts of substituen ts: 2a – OCH₂C₆H₅: 74.91 t, 73.60 t, SCH₂CH₃: 24.11

t, 14.94 q, CH₃SO₂O: 38.63 q; 2b – OCH₂C₆H₅: 73.56 t, SCH₂CH₃: 24.14 t, 14.95 q,

CH₃SO₂O: 38.73 q, OCH₂CH=CH₂: 73.21 t, 133.42 d, 117.81 t; 3a – OCH₂C₆H₅: 73.65 t,

70.96 t, SCH₂CH₃: 24.30 t, 14.88 q, OAc: 170.44 s, 20.95 q; 3b – OCH₂C₆H₅: 73.63 t,

SCH₂CH₃: 24.31 t, 14.90 q, OAc: 170.27 s, 20.86 q, OCH₂CH=CH₂: 70.16 t, 133.91 d, 117.52 t;

4 – α-an om er – OCH₂C₆H₅: 71.06 t, 73.66 t, OAc: 169.95 s, 23.89 q; 4 – β-an om er –

OCH₂C₆H₅: 71.22 t, 73.72 t, OAc: 170.27 s, 23.89 q; 5a – J_C-1,F= 228.1, J_C-2,F= 25.7, J_C-5,F

=

2.2, OCH₂C₆H₅: 73.64 t, 71.24 t, OAc: 170.07 s, 20.80 q; 5b – J_C-1,F= 214.3, J_C-2,F= 21.5,

J_C-3,F= 9.4, J_C-5,F= 5.0, OCH₂C₆H₅: 73.74 t, 71.28 t, OAc: 170.22 s, 20.78 q; 6 – OCH₂C₆H₅:

73.70 t, 71.20 t, OAc: 170.40 s, 20.91 q; 7 – OCH₂C₆H₅: 73.54 t, 71.28 t, OAc: 170.34 s,

20.87 q, OC(NH)CCl₃: 160.90 s, 93.21 s; 8 – OCH₂C₆H₅: 73.67 t, 71.24 t, SCH₂CH₃: 23.69 t,

14.87 q; 9a – OCH₂CH₂CH₂CH=CH₂: 68.94 t, 28.41 t, 29.75 t, 137.71 d, 114.61 t;

9b – OCH₂C₆H₅: 73.65 t, OAc: 170.31 s, 20.84 q, OCH₂CH₂CH₂CH=CH₂: 68.98 t, 28.48 t,

29.78 t, 137.74 d, 114.61 t, OCH₂CH=CH₂: 70.25 t, 133.98 d, 117.41 t; 10a – OCH₂C₆H₅:

73.68 t, 71.29 t, OCH₂CH₂CH₂CH=CH₂: 68.57 t, 28.48 t, 29.81 t, 137.85 d, 114.53 t;

10b – OCH₂C₆H₅: 73.70 t, OCH₂CH₂CH₂CH=CH₂: 68.60 t, 28.54 t, 29.83 t, 137.87 d,

114.54 t, OCH₂CH=CH₂: 70.37 t, 133.88 d, 117.86 t; 11 – OCH₂C₆H₅: 73.70 t, 72.23 t,

OCH₂CH₂CH₂CH=CH₂: 68.80 t, 28.45 t, 29.80 t, 137.88 d, 114.49 t, OSi(CH₃)₃: 0.57 q.

b

c

Altern ative assign m en t of ch em ical sh ifts. Overlapped by solven t sign al.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1934

Veselý, Ledvina, Jindřich, Trnka, Šaman:

8 h . Th e apparatus was flush ed with argon (2×) an d dry dich lorom eth an e (5 m l) was added

th rough th e septum . Th e m ixture was stirred at room tem perature for 1 h , an d a solution of

glycosyl brom ide 4, fresh ly prepared from 3a (230 m g, 0.4 m m ol) an d dich lorom eth an e

(4 m l), was added at –15 °C un der stirrin g th rough th e septum durin g 1 h an d th en th e stir-

rin g was con tin ued at room tem perature for an oth er 10 h . Progress of th e reaction was m on -

itored on TLC in toluen e–eth yl acetate (5:1). Pyridin e (1.5 m l) was added an d after 1 h stir-

rin g at room tem perature, th e m ixture was diluted with ch loroform (12 m l) an d filtered

TABLE VI

Ch aracteristic ¹³C NMR ch em ical sh ifts of com poun ds 12–17b^a

Carbon

12

14

16a

16b

16c

17a

17b

1

80.18

50.77

75.92

73.49

77.14

69.44

99.5

52.94

72.72

65.74

71.67

68.00

–

80.77

54.74

78.82

76.03

77.67

69.45

97.09

56.24

76.87

72.73

73.42

68.25

–

98.02

52.13

75.32

74.54

73.58

69.72

99.86

52.80

72.69

65.70

71.57

68.14

67.95

28.37

29.75

137.96

114.34

98.15

52.27

70.25

75.26

73.60

69.77

99.85

51.14

67.81

66.52

75.26

61.38

68.19

28.41

29.76

137.91

114.39

98.24

52.30

75.50

74.54

73.75

69.86

99.64

52.82

72.79

65.81

71.69

68.18

67.93

28.49

29.82

138.03

114.38

98.04

51.87

75.66

69.68

72.72

66.94

97.62

52.65

70.68

66.77

68.19

68.13

67.24

29.69

29.96

138.08

114.48

98.50

52.60

76.18

73.06

73.30

69.38

104.62

60.81

72.74

77.96

69.03

62.57

68.67

28.47

29.79

137.87

114.49

2

3

4

5

6

1′

2′

3′

4′

5′

6′

1′′

2′′

3′′

4′′

5′′

–

a

¹³C ch em ical sh ifts of arom atic carbon s from protectin g groups are n ot given . Addition al

¹³C NMR ch em ical sh ifts of substituen ts: 12 – OCH₂C₆H₅: 73.59 t, 72.74 t, 71.43 t, 71.03 t,

SCH₂CH₃: 22.49 t, 14.63 q, OAc: 170.59 s, 21.03 q; 14 – OCH₂C₆H₅: 74.58 t, 73.90 t, 73.55 t,

72.67 t, SCH₂CH₃: 23.62 t, 14.86 q, OAc: 169.63 s, 20.89 q; 16a – OCH₂C₆H₅: 73.34 t, 71.60 t,

70.93 t, 68.14 t, OAc: 170.58 s, 20.99 q; 16b – OCH₂C₆H₅: 73.47 t, 71.91 t, OAc: 170.39 s,

170.35 s, 169.92 s, 20.74 q, 20.66 q, 20.57 q; 16c – OCH₂C₆H₅: 73.62 t, 73.42 t, 71.00 t,

OAc: 170.56 s, 20.97 q, OCH₂CH=CH₂: 71.34 t, 134.28 d, 117.63 t; 17a – OCH₂C₆H₅:

73.46 t, 73.11 t, 71.36 t, 71.13 t, OAc: 170.28 s, 21.27 q; 17b – OCH₂C₆H₅: 73.60 t, 71.97 t,

OAc: 170.43 s, 170.39 s, 170.31 s, 20.78 q, 20.69 q, 20.50 q.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1935

th rough Celite. Th e filtrate was evaporated. Th e residue was separated by ch rom atograph y

on a silica gel colum n (15 g) in toluen e–eth yl acetate (10:1) to give 122 m g (57%,) of a syr-

upy com poun d 16a an d 45 m g (21%) of a syrupy com poun d 16b.

Method B: Com poun ds 3a (234 m g, 0.4 m m ol) an d 10a (112 m g, 0.2 m m ol) were dried in

an apparatus equipped with a septum by co-distillation with dry ben zen e (3 × 3 m l), added

th rough th e septum . Crush ed m olecular sieves 4 Å (300 m g) were added an d dryin g was

con tin ued at room tem perature an d 20 Pa for 8 h . Th e apparatus was flush ed with argon

(2×) an d dry dich lorom eth an e (4 m l) was added th rough th e septum . After dissolution ,

m eth yl triflate (60 µl, 0.53 m m ol) was added un der stirrin g at room tem perature th rough

th e septum an d th e stirrin g was con tin ued at th e sam e tem perature for 2 days. Progress of

th e reaction was m on itored as described in m eth od A. Th e m ixture was taken between ch lo-

roform (20 m l) an d saturated aqueous sodium h ydrogen carbon ate (10 m l) an d organ ic layer

was separated, wash ed with water (2 × 5 m l), dried over an h ydrous m agn esium sulfate an d

evaporated in vacuo. Th e residue was separated by a colum n ch rom atograph y as described

in m eth od A, to give 90 m g (42%) of a syrupy com poun d 16a, 45 m g (21%) of a syrupy

com poun d 16b an d 25 m g (22%) of startin g com poun d 10a.

Method C: Com poun d 10a (112 m g, 0.2 m m ol) was dried in an apparatus equipped with a

septum by co-distillation with dry ben zen e (3 × 3 m l). Com poun d 5b (213 m g, 0.4 m m ol)

was added an d dryin g was con tin ued at room tem perature an d 20 Pa for an oth er 8 h . Th e

apparatus was flush ed with argon (2×) an d th e m ixture was dissolved in dry dieth yl eth er

(6 m l) added th rough th e septum . Th e obtain ed solution was added th rough th e septum to

a stirred m ixture of titan ium (IV) fluoride (87 m g, 0.7 m m ol) an d m olecular sieves 3 Å (1.5 g)

un der argon in an apparatus equipped with th e septum at 0 °C. Th e stirrin g was th en con -

tin ued at room tem perature for 18 h . Progress of th e reaction was m on itored as described in

m eth od A. Th e reaction m ixture was worked up by th e sam e procedure as is given in proce-

dure A, to afford 51 m g (24%) of a syrupy com poun d 16a, 36 m g (17%) of a syrupy com -

poun d 16b, 31 m g (15%) of a syrupy com poun d 5a, 23 m g (21%) of startin g com poun d 10a

an d 74 m g (35%) of startin g com poun d 5b.

Method D: Com poun d 10a (112 m g, 0.2 m m ol) was dried in an apparatus equipped with a

septum by co-distillation with dry ben zen e (3 × 3 m l), added th rough th e septum . Com -

poun d 5b (120 m g, 0.22 m m ol) was added an d th e dryin g was con tin ued at room tem pera-

ture an d 20 Pa for an oth er 8 h . Th e apparatus was flush ed with argon (2×) an d th e m ixture

was dissolved in dry dich lorom eth an e (4 m l) added th rough th e septum . Th e obtain ed solu-

tion was added th rough th e septum to a stirred m ixture of bis(cyclopen tadien yl)zircon ium

dich loride (350 m g, 1.2 m m ol), silver perch lorate (250 m g, 1.2 m m ol) an d crush ed m olecu-

lar sieves 4 Å (200 m g) in dry dich lorom eth an e (4 m l) un der argon an d at –20 °C in a appa-

ratus equipped with a septum . Th e m ixture was stirred at –20 °C for 2 h , an d th en ch loro-

form (20 m l) an d saturated aqueous sodium h ydrogen carbon ate (6 m l) were added. After

warm in g to room tem perature th e m ixture was filtered an d organ ic layer was separated,

wash ed with water (2 × 10 m l), dried over an h ydrous m agn esium sulfate an d evaporated in

vacuo. Th e residue was separated by a colum n ch rom atograph y as described in m eth od A,

to give 77 m g (36%) of a syrupy com poun d 16a, 30 m g (14%) of a syrupy com poun d 16b,

40 m g (36%) of startin g com poun d 10a an d 15 m g (13%) of startin g com poun d 5b.

Method E: Com poun ds 11 (126 m g, 0.2 m m ol) an d 5b (213 m g, 0.4 m m ol) were dried in

an apparatus equipped with a septum by co-distillation with dry ben zen e (3 × 3 m l). Th e ap-

paratus was flush ed with argon (2×) an d dry aceton itrile (6 m l) was added th rough th e sep-

tum . After dissolution , th e m ixture was cooled to –45 °C an d trim eth ylsilyl trifluoro-

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

1936

Veselý, Ledvina, Jindřich, Trnka, Šaman:

m eth an esulfon ate (10 µl, 0.05 m m ol) was added un der stirrin g th rough th e septum . Th e

m ixture was stirred at –20 °C for 2 h an d th an at room tem perature for 3 days. Progress of

th e reaction was m on itored as described in m eth od A. Th e m ixture was filtered th rough

Celite, taken between toluen e (30 m l) an d saturated aqueous sodium h ydrogen carbon ate

(10 m l), an d organ ic layer was separated, wash ed with water (2 × 10 m l), dried over an h y-

drous m agn esium sulfate an d evaporated in vacuo. From th e com plex reaction m ixture

24 m g (11%) of a syrupy com poun d 16a was isolated by a colum n ch rom atograph y as de-

scribed in m eth od A, followed by HPLC separation on a silica gel colum n (5 µm ) in h ex-

an e–eth yl acetate (3:1).

Method F: Com poun ds 7 (270 m g, 0.4 m m ol) an d 10a (112 m g, 0.2 m m ol) were dried in

an apparatus equipped with a septum by co-distillation with dry ben zen e (3 × 3 m l), added

th rough th e septum . Crush ed m olecular sieves 4 Å (300 m g) were added an d dryin g was

con tin ued at room tem perature an d 20 Pa for 8 h . Th e apparatus was flush ed with argon

(2×) an d dry dich lorom eth an e (5 m l) was added th rough th e septum . After dissolution , th e

m ixture was cooled to –45 °C an d 1 M solution of boron trifluoride eth erate in dich loro-

m eth an e (100 µl, 0.1 m m ol) was added th rough th e septum un der stirrin g. Th en th e m ix-

ture was stirred at room tem perature for 3 days. Progress of th e reaction was m on itored as

described in m eth od A. Th e m ixture was taken between ch loroform (20 m l) an d saturated

aqueous sodium h ydrogen carbon ate (10 m l), an d organ ic layer was separated, wash ed with

water (2 × 5 m l), dried over an h ydrous m agn esium sulfate an d evaporated in vacuo. Th e res-

idue was separated by a colum n ch rom atograph y as described in m eth od A, to give 64 m g

(30%) of a syrupy com poun d 16a, 24 m g (11%) of a syrupy com poun d 16b an d 54 m g

(48%) of startin g com poun d 10a.

Method G: Com poun ds 7 (270 m g, 0.4 m m ol) an d 10a (112 m g, 0.2 m m ol) were dried in

an apparatus equipped with a septum by co-distillation with dry ben zen e (3 × 3 m l), added

th rough th e septum . Crush ed m olecular sieves 4 Å (300 m g) were added an d dryin g was

con tin ued at room tem perature an d 20 Pa for 8 h . Th e apparatus was flush ed with argon

(2×) an d dry dich lorom eth an e (5 m l) was added th rough th e septum . After dissolution , th e

m ixture was cooled to –45 °C an d trim eth ylsilyl trifluorom eth an esulfon ate (80 µl,

0.4 m m ol) was added un der stirrin g th rough th e septum . Th e m ixture was stirred at th e

sam e tem perature for 12 h an d th en at room tem perature for 3 days. Progress of th e reaction

was m on itored as described in m eth od A. Th e m ixture was filtered th rough Celite, partion ed

between ch loroform (20 m l) an d saturated aqueous sodium h ydrogen carbon ate (10 m l), an d

organ ic layer was separated, wash ed with water (2 × 5 m l), dried over an h ydrous m agn esium

sulfate an d evaporated in vacuo. Th e residue was separated by a colum n ch rom atograph y as

described in m eth od A, to give 105 m g (49%) of a syrupy com poun d 16a an d 24 m g (11%)

of a syrupy com poun d 16b.

Compound 16a: [α]_D+13 (c 0.2, ch loroform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI.

For C₆₃H₆₂N₂O₁₄calculated: relative m olecular m ass 1071.2, m on oisotopic m ass 1070.4.

ESI MS, m/z: 1093.8 [M + Na]⁺. For C₆₃H₆₂N₂O₁₄(1071.2) calculated: 70.64% C, 5.83% H,

2.62% N; foun d: 70.28% C, 6.02% H, 2.51% N.

Compound 16b: [α]_D+46 (c 0.7, ch loroform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI.

For C₆₃H₆₂N₂O₁₄calculated: relative m olecular m ass 1071.2, m on oisotopic m ass 1070.4.

ESI MS, m/z: 1093.5 [M + Na]⁺. For C₆₃H₆₂N₂O₁₄(1071.2) calculated: 70.64% C, 5.83% H,

2.62% N; foun d: 70.32% C, 5.91% H, 2.49% N.

Collect. Czech. Chem. Commun. (Vol. 69) (2004)

2-Amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino-2-deoxy-β-D-galactopyranosides

1937

Pen t-4-en yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran osyl-

(1→4)-3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (17a) an d

Pen t-4-en yl 4-O-Acetyl-3,6-di-O-ben zyl-2-deoxy-2-ph th alim ido-α-D-galactopyran osyl-

(1→4)-3-O-allyl-6-O-ben zyl-2-deoxy-2-ph th alim ido-β-D-galactopyran oside (17b)

Com poun d 10b (102 m g, 0.2 m m ol) was dried in an apparatus equipped with a septum by

co-distillation with dry ben zen e (3 × 3 m l), added th rough th e septum . Silver carbon ate

(276 m g, 1 m m ol), silver perch lorate (48 m g, 0.23 m m ol) an d m olecular sieves 4 Å (300 m g)

were added an d dryin g was con tin ued at room tem perature an d 20 Pa for an oth er 8 h . Th e

apparatus was flush ed with argon (2×) an d dry dich lorom eth an e (3 m l) was added th rough

th e septum . Th e m ixture was stirred at room tem perature for 1 h an d a solution of glycosyl

brom ide 4, fresh ly prepared from 3a (173 m g, 0.3 m m ol), in dry dich lorom eth an e (3 m l)

was added un der stirrin g th rough th e septum durin g 1 h an d th e stirrin g was con tin ued

at room tem perature for an oth er 10 h . Progress of th e reaction was m on itored on TLC in

toluen e–eth yl acetate (5:1). Pyridin e (1.5 m l) was added an d after 1 h stirrin g at room tem -

perature, th e m ixture was diluted with ch loroform (12 m l) an d filtered th rough Celite. Th e

filtrate was evaporated. Ch rom atograph y of th e residue on a silica gel colum n (15 g) in

oluen e–eth yl acetate (10:1) followed by HPLC separation on a silica gel colum n (5 µm ) in

h exan e–eth yl acetate (4:1) afforded 35 m g (17%) of a syrupy com poun d 17a an d 22 m g

(11%) of a syrupy com poun d 17b an d 42 m g (43%) of startin g com poun d 10b.

Compound 17a: [α]_D–39 (c 0.2, ch loroform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI.

For C₅₉H₆₀N₂O₁₄calculated: relative m olecular m ass 1021.1, m on oisotopic m ass 1020.4.

ESI MS, m/z: 1043.3 [M + Na]⁺. For C₅₉H₆₀N₂O₁₄(1021.1) calculated: 69.40% C, 5.92% H,

2.74% N; foun d: 69.28% C, 6.10% H, 2.66% N.

Compound 17b: [α]_D+128 (c 0.2, ch loroform ). ¹H NMR: see Table IV, ¹³C NMR: see Table VI.

For C₅₉H₆₀N₂O₁₄calculated: relative m olecular m ass 1021.1, m on oisotopic m ass 1020.4.

ESI MS, m/z: 1043.5 [M + Na]⁺. For C₅₉H₆₀N₂O₁₄(1021.1) calculated: 69.40% C, 5.92% H,

2.74% N; foun d: 69.33% C, 6.16% H, 2.62% N.

This work was supported by the Grant Agency of the Czech Republic (grant No. 203/00/0071), by

the Ministry of Education, Youth and Sports (grant No. 1131 00001) and Research Project Z4/055/905,

by the Grant Agency of the Charles University (grant No. 244/2003).

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Collect. Czech. Chem. Commun. (Vol. 69) (2004)

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Synthesis of 2-amino-2-deoxy-β-D-galactopyranosyl-(1→4)-2-amino- 2-deoxy-β-D-galactopyranosides: Using various 2-deoxy-2-phthalimido-D- galactopyranosyl donors and acceptors

DOI: 10.1135/cccc20041914

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Full text of DOI:10.1135/cccc20041914

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