• 検索結果がありません。

A convenient synthetic method of 2-substituted indoles and its applcation for the synthesis of natural alkaloid, borrerine

N/A
N/A
Protected

Academic year: 2022

シェア "A convenient synthetic method of 2-substituted indoles and its applcation for the synthesis of natural alkaloid, borrerine"

Copied!
4
0
0

読み込み中.... (全文を見る)

全文

(1)

A convenient synthetic method of 2‑substituted indoles and its applcation for the synthesis of natural alkaloid, borrerine

著者 Somei Masanori, Sayama Shinsuke, Naka Katsumi, Yamada Fumio

journal or

publication title

Heterocycles

volume 27

number 7

page range 1585‑1587

year 1988‑01‑01

URL http://hdl.handle.net/2297/4313

(2)

HETEROCYCLES,Vol27,No.7,7988

ACONVENエENTSYNTHETエCMETHODOF2-SUBSTエmUmEDエNDOLESANDエTS

APPL工CATエONFORTHESYNTHESエSOFNATURALALKALOエD,BORRERエNE1

MasanoriSomei,*ShinsukeSayama,KatsumiNaka,andFumioYamada FacultyofPharmaceuticalSciences,KanazawaUniversity

l3-1Takara-machi,Kanazawa920,.apa、

Abstract-Asimp1esyntheticmethodof2-substituted indolesisdeveloped・TotalsynthesisoEnaturalalkaloid,

borrerine,isalsoreported.

mthiscommunication,wedescribeaversat1letwostepsYntheticmethodwhichcan providesynthetica11yuseful2-substitutedindoles,anditsaPP1icationforthe

synthesisofnatura1alkaloid,borrerme(7c).2

commerciallyavailable2-oxindole(1)ledto2-bromo-3-indo1ecarboxaldehyde(2) ヘグ

in77gyieldaccordin9toSchulte’sprocedure、3エnordertointroduceacarbonside chaindirect1yintothe2-position○だ2,improvedHeckreaction4a’b seemedtobe

へ夕

4a-dHowever,

promisingamongvariouspalェadiumcatalyzedcrosscouP1ingreactions.

R3Sn-R1

CR]〔:iLLCEi。〔;vo

○TLo-

。「、‐LOHP-B

,lKCOOMeP-B

1}

02

○甲

、=N

dl-〃

’3

ヘヴ

l-c【】【

-1585-

(3)

theHeckreactiono定2with2-methyl-3-buten-2-oエproducedthedesired2-(3-hydroxy-

3-methy1-1-buten-1-yl)-3-indolecarboxa1dehyde(3a,、p190.5-193.C)inpooryield

andtheyie1dcouldnotbeincreasedabovel58unde]ごvariousreactionconditions・

Ontheotherhand,modiどiedStil1e'sreaction4cwasだ。undtomeetourend・Thus,3a

wasobtainedin878yiLe1dbythereactionof2with(3-hydroxy-3-methyエーユーbuten-l-

yl)tributy1tin(4a)5inthepresenceoftetra-n-butylalnInon1umchlorideandacata-

lyticamount。fpal1adiumacetate・Similarly,thereactionof2vvithtinreagents,

suchas4b,64c,4.,74e,and4f,7afEorded3b(mp26エー262°C),3c(mp260.5-263°C),

~~

3.(mp246-246.5°C),3e(mp207-208.5°C),and3f(mp226-227oC)in678,688,388,

タレ ヘク

398,and58yields,respective1y・Zknattempttoimprovetheyieldof3fiscur-

rentlyunderinvestigation・

Withthedesiredbui1dingblocks(3a-f)forvarious2-substitutedindolesinhand,

〃、=~

wenexttriedatota1synthesisofborrerine(7c).2First,3awasconvertedto5

nヴ グレ

(mp246-247oC)in86号yieldbythereactionwithnitromethaneinthepresenceof ammoniumacetate・Subsequentreductionof5withsodiumborohydrideinmethano1ar-

Eorded6(mp122-123oC)in80gyield・Next,ourreductiveaminocyclizationmethod8

いず

(reE1uxingwithzincinmethanolichydroch1。ricacid)wassuccessEu11yapp1iedto6

affording酉(、p162-164°C,1it、2bmp158-159oC)in508Yie1d・Treatmentof7awith

methy1chloroformategave858yieldof7P(mp188.5-189°C,1it、2bmpl80-181oC),

whichfina11yエedtoborrerine(7s,、p107-108°C,1it、2bmp1O2-103oC)in708

yie1dbythereductionwith1ithiumaluminumhydrideinanhydroustetrahydrofuran・

Spectraldataof7cwereidenticalwiththoseofborrerinewhichwassynthesizedby

2b'9 Sakaiandco-workers・

Bioエ。gica1evaluationsofnewcompoundsandthetota1synthesisoEotherreエated naturalalkaloidsarecurrentlyinprogress.

ACKNOWLEDCEMENT

TheauthorsexpresstheircordiaエgratitudetoProf.S・Sakai,ChibaUniversity,

造。rkind1ysendingusspectraユdataandauthenticsampユeofborrerine.

REFERENCESANDNOTES

ェ・ThisreportispartXLVo造theseriesentit1edooTheChemistryofェndo1esuo・

PartXLエV:M、Somei,M・Wakida,andT・Ohta,Chem・Pharm、Bull.,36,1162(1988). 2.a)。.L・Pousset,。.Kerharo,G・Maynart,X・Monseur,Z1.Cav6,andR・Goutarel,

ElユXL2E」ユニ型ニューム2,浬,2308(1973);b)E・Yamanaka,N・Shibata,andS・Sakai,

-1586-

(4)

HETEROCYCLES,Vol2ZNo.Z7988

旦皀上里gEエユニニ,客,271(1984);。)M・D66deMaindrevil1e,。.L6W,F・Til1eCIuin,

andM、Koch,。.Nat・Pro。.,46,310(1983);。)エsoborrerinesynthesis:P.A、

GriecoandA、Bahsas,L-g92gL-g型.,薯,1378(1987).

3.K.E・Schulte,。.Reisch,andU・Stoess,Arch・Pharmaz.,305,523(1972).ハツーヒ

4.a)R、F・Heck,Pa1ladiumReagentsinOrganicSYnthesis,ZAcademicPressエnc.

(London)Ltd.,1985;b)T、。e鉦ery,。.Che、、SOC.,Chem・Commun.,1984,1287;

ヘグーー-

M.Somei,T・Hasegawa,T・Suzuki,and1U、Wakida,Abstractso缶Papers,ThelO5th AnnualMeetingoEPharmaceuticalSocietyoゼコapan,Kanazawa,Apriユエ985,p・679;

c)。.K・Stil1e,Angew・Chem・エnt2Ed・IZngL,25,508(1986);d)M・Somei,T・へ'

Hasegawa,andC・Kaneko,11目些竺2ニユニュニニ,割,1983(1983);M・Somei,H・Amari,and

Y・Makita,Che、、Pharm・Bull.,34,3971(1986);M・Somei,F・Yamada,andK・Naka,ヘジ

ュbid.,35,1322(1987).

デー

5.H・回・Ensley,R、R・Buescher,andl(・Lee,。.Org1Chem.,47,404(1982).へ声

6.コ.K・StilleandB.L・Groh,。.ZAm・Chem・SOC.,109,813(1987).~、ハジ 7.Y、YamamotoandZk・Yanagi,Che、、Pharm・Bull.,30,1731(1982).へP

F・Yamada,T・Hasegawa,M・Wakida,M・Sugiyama,andM・Somei,IIeterocycユeS,

24,1223(1986);F・Yamada,Y・Makita,T・Suzuki,andM・Somei,Chem・Pharm.

8.

穴シ

Bull.,33,2162(1985). PLP

9.ldixedmeltingpointoE7candborrerineshowednodepressユ。n.Borrerineand7cAP へ>

meltedonceatabout57--59oCandgraduallysolidiだied,andthenfinallymelted

atlO7-108oC.

Received,11thNarch,1988

-1587-

参照

関連したドキュメント