Synthese von 1,1′-Biphenyl-3-carbonsäure-und 3,5-dicarbonsäurederivaten unter Verwendung von Ethoxymethylenmalononitril

Reaction of ethoxymethylenemalononitrile with ethyl 4-phenylacetoacetate leads to ethyl 1,1-biphenyl-6-amino-5-cyano-2-hydroxy-3-carboxylate (3). Acid or basic hydrolysis of the ester and cyano group of3 affords the new derivatives4,5 and6.7 a, b are obtained bySandmeyer-reaction of3. Basic hydrolysis of7 a gives the 3,5-dicarboxylic acid derivative8.

     

Struktur/Geruchs-Beziehungen von mit β-Santalol verwandten Verbindungen:E-Homo-β-santalol undE-Dehydrohomo-β-santalol

Summary To study the structure/odour relationships of -santalol analogues two homologous -santalol derivatives5 and6 were synthesized. The key steps thereby were the -alkylation of the bicyclic starting ketones8 and14 accomplished by using more drastic conditions as usual. The odours of5 and6 are described in detail.

Auszugsweise vorgetragen am 19th International Symposium on Essential Oils and Other Substrates, 9. September 1988, Greifensee/Dübendorf, Schweiz     

Über die Synthese von Dihydro-1,2,3,5-thiatriazol-1,1-dioxiden, 2. Mitt.

By reaction of several N-phenyl-benzamidrazones with SO₂F₂ 2-phenyl-2,5-dihydro-1,2,3,5-thiatriazole-1,1-dioxides2 a–c are formed. By reaction of N,N-diethyl-N-chlorosulfonyl-chloroformamidine8 with hydrazines the corresponding 4-diethylamino-substituted derivatives9 a–d are obtained. Methylation of2 b yields two isomeric products5 and6, whereas by methylation of9 d only one product9 b is obtained.

     

Anilinochinone und Chinonanile aus 4,4′-Bi-(1,2-naphthochinon)

4,4-Bi-(1,2-naphthoquinone) (1) reacts with several aromatic amines to yield the anilino-quinones2 a-k. Compound2 a is characterized by the binaphthoquinone dioxime6 and the semicarbazide8. The reductive benzoylation of2 a gives the benzoylester5. The aminoquinones2 a-g can be oxidized yielding the quinone-aniles3 a-g. IR and MS spectra of2 and3 are discussed.

     

Reaction of CH acids with 2-arylidenecycloalkanones: Synthesis of β-keto acid anilide derivatives of naphthalene,indene, fluorene,and phenanthrene

Summary 2-Arylidene-cyclohexanone1, -cyclopentanone2, -1-indanone3 and-1-tetralone4 react with acetoacetanilide5 yielding 2-oxo-4-aryl-3-carboxylic acid anilides derivatives of naphthalene7, indene8, fluorene9 and phenanthrene10. Reaction of1 and3 with benzoylacetanilide6 yields the corresponding Michael adducts11 and12.

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Reaktion von CH-Säuren mit 2-Arylidencycloalkanonen. Synthese von -Ketosäureanilid-Derivaten von Naphthalin, Inden, Fluoren und Phenanthren

Zusammenfassung 2-Arylidencyclohexanone1, -cyclopentanone2, -1-indanone3 und -1-tetralone4 reagieren mit Acetoacetanilid5 unter Bildung von 2-Oxo-4-aryl-3-carbonsäureanilid-Derivaten von Naphthalin7, Inden8, Fluoren9 und Phenanthren10. Die Reaktion von1 und3 mit Benzoylacetanilid6 ergibt die entsprechenden Michael-Addukte11 und12.

     

Strukturelle Abwandlungen anN-Acetylneuraminsäure, 4. Mitt. Transformationen am Diethyl-dithioketal desN-Acetylneuraminsäure-γ-lactons

Partial protection of diethyldithioketal ofN-acetylneuraminic acid--lactone using one or two equivalents oft-butyldimethylchlorosilane leads to the 9-O-silyletherderivative7 and the 8,9-bis-O-silylderivative5, resp. The reaction of1 as well as7 with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TIPSiCl₂) yields selectively the protected products4 and9. The 9,8,7,6-tetra-O-acetyl-N-acetylneuraminic acid--lactone derivative3 is formed by the oxidative desulfurazation of the peracteylated form of1 (i. e.2) by means ofNBS. By reaction of5 withTPPDEAD the 6,7-carbonato compound6 arises instead of the expected 6,7-epoxyderivative. The analogous carbonate8 is formed by treating7 with bisimidazolylcarbonate.

     

Addition products of hydrazine derivatives to azo-alkenes,part V: The reaction of α-(1-phenylhydrazino)alkanone phyenylhydrazones with acids and acid derivatives

Summary The bifunctional title compounds2 react with acylating, carbamoylating and sulfonylating reagents mostly at the primary amino group of the hydrazine function. Both functional groups of2 are attacked by N,N-carbonyldiimidazole converting it into 1H-1,2,4,5-tetrazepin-3-one derivatives8. The acid-induced 1,4-elimination of phenylhydrazine from2 gives rise to the formation of phenylosazones3. In the presence of thiocyanic acid the intermediately formed phenylazo-alkenes1 undergo [3+2]-cycloaddition furnishing 1-anilino-imidazoline-2-thiones13.

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Additionsprodukte von Hydrazin-Derivaten an Phenylazo-alkene, 5. Mitt.: Umsetzung von -(1-Phenylhydrazino)alkanon phenylhydrazonen mit Säuren und Säurederivaten

Zusammenfassung Die bifunktionellen Titelverbindungen2 reagieren mit Acylierungs-, Carbamoylierungs-und Sulfinylierungs-Reagenzien meist an der primären Amino-Gruppe der Hydrazin-Funktion. N,N-Carbonyldiimidazol greift beide funktionelle Gruppen von2 an und bedingt die Umwandlung in 1H-1,2,4,5-Tetrazepin-3-on-Derivate8. Die säureinduzierte 1,4-Eliminierung von Phenylhydrazin aus2 führt zur Bildung der Phenylosazone3. In Gegenwart von Thiocyansäure erfolgt [3+2]-Cycloaddition an die intermediär gebildeten Phenylazo-alkene1, sodaß 1-Anilino-imidazolin-2-thione13 entstehen.

     

Synthesis of 2′,3′-dideoxynucleosides from 5-alkoxymethyluracils

Summary A modified synthesis of protected 2,3-dideoxyribose5 starting fromL-glutamic acid (1) is described. Reaction of5 with silylated 5-hydroxymethyluracil7 a and 5-alkoxymethyluracils7 b–e in the presence of trimethylsilyl triflate afforded an anomeric mixture of 2,3-dideoxyuridine derivatives8 a–e and9 a–e. Deprotection with methanolic ammonia and separation by chromatography gave the corresponding nucleosides10 a–e and11 a–e. Treatment of9 b–e with tri(1H-1,2,4-triazol-1-yl)phosphine oxide and subsequent reaction of12 b–e with ammonia in dioxane afforded the cytosine derivatives13 b–e which on treatment with methanolic ammonia gave the corresponding 2,3-dideoxycytidine derivatives14 b–e and15 b–e. In contrast with the parent compounds, these alkoxymethyl derivatives had no appreciable activity against human immunodeficiency virus (HIV-1).

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Synthese von 2,3-Dideoxynucleosiden aus 5-Alkoxymethyluracilen

Zusammenfassung Ausgehend vonL-Glutaminsäure (1) wird eine modifizierte Synthese von geschützter 2,3-Dideoxyribose (5) beschrieben. Reaktion von5 mit silyliertem 5-Alkoxymethyluracilen7 b–e in Gegenwart von Trimethylsilyltriflat ergab anomere Mischungen der 2,3-Dideoxyuridinderivate8 a–e und9 a–e. Abspaltung der Schutzgruppe mit methanolischen Ammoniak und chromatographische Trennung ergab die entsprechenden Nucleoside10 a–e und11 a–e. Behandlung von9 b–e mit Tri(1H-1,2,4-triazol-1-yl)phosphinoxid und nachfolgende Reaktion von12 b–e mit Ammoniak in Dioxan ergab die Cytosinderivate13 b–e, welche nach Behandlung mit methanolischem Ammoniak die entsprechenden 2,3-Dideoxycytidinderivate14 b–e und15 b–e ergaben. Im Gegensatz zur Stammverbindung hatten diese Alkoxymethylderivate keine nennenswerte Wirksamkeit gegen den menschlichen Immunschwächevirus (HIV-1).

     

Aromatische Spirane, 14. Mitt. Darstellung von 2,2′-Spirobi-(s-hydrindacen) und seinen Vorstufen

The title compound35 was prepared by catalytic reduction of the diones29 a and11a.29 a was synthesized by systematic anellation of fivemembered rings to the positions 5,6 and 5,6, resp., of 2,2-spirobiindane. The preparation of11 a was achieved byFriedel-Crafts cyclisation of bis-(5-indanylmethyl)-malonic acid. s-Hydrindacene-1-one5 a was prepared as a precursor for the synthesis of11 a (see forthcoming publication) and its derivates as models for corresponding anellation and substitution reactions.

     

A study on the doubleMannich reaction with 1,3-diphenylacetone

DoubleMannich reaction of the title compound1 with morpholine acetate in ethanol gave the symmetrical bis-base2, whereas such reaction in acetic acid afforded the vinyl-ketonic base3. Reactions of3 with morpholine, piperidine, thiophenol and dimethyl phosphite were investigated.Mannich reaction of2 with primary amines gave di-basically substituted -piperidones6a-b. Compound1 reacts with ethylenediamine and formaldehyde to give the diazatricyclic system7.

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Untersuchungen zur doppeltenMannich-Reaktion mit 1,3-Diphenylaceton

Zusammenfassung Die Doppel-Mannichreaktion der Titelverbindung1 ergab mit Morpholinacetat in Ethanol die symmetrische Bis-Base2, in Essigsäure erhielt man jedoch die Vinyl-keton-base3. Die Reaktionen von3 mit Morpholin, Piperidin, Thiophenol und Dimethylphosphit wurden untersucht. DieMannich-Reaktion von2 mit primären Aminen ergab di-basisch substituierte -piperidone6a-b. Verbindung1 reagiert mit Ethylendiamin und Formaldehyd unter Ausbildung eines Diaza-tricyclischen Systems7.

     

Synthese und Reaktionen von 2-Amino-1-aryl-5-oxo-Δ2-pyrrolin-3-carbonitrilen

Summary The reaction of malononitrile with -chloro acetanilides1 in presence of potassium carbonate yields the 1-aryl-5-oxo-²-pyrrolin-3-carbonitriles2, in presence of triethylamine the 4,6-diamino-1-aryl-2-oxo-2,3-dihydropyrrolo[2,3-b]pyridin-5-carbonitriles3 are formed. From 2-chloroacetylamino-benzencarbonitrile and malononitrile the 5-amino-1-oxo-1,2-dihydropyrrolo[1,2-a]chinazolin-3-carbonitrile (4) arise. Analogously from the 2-chloroacetylamino-thiophen-3-carbonitries5 the 7,8-dihydro-thieno[3,2-e]pyrrolo[1,2-a]pyrimidine derivatives6 are obtainable. Hydrolysis of2 a by treatment with hydroxide or acid, respectively, yields the 1,1,2-ethanetricarboxylic acid and derivatives9 a,b. Phenyldiazonium salt reacts with2 to form the triazene 7 only.

     

Heterocyclically bridged tricyclic β-lactames: A simple synthesis of 1,2,2a,8a-tetrahydro-3-oxa-1-aza-cyclobuta[b]naphthalen-2-ones

Summary The tricyclic 3,4-bridged -lactames7 and8 containing a hetero atom as 3-substituent of the azetidin-2-one ring were synthesized by intramolecular radical cyclization usingcis-substituted 3-(2-bromo-aryloxy)-azetidine-2-ones6 as precursors. These precursors were generated by stereospecific acid chloride-imine reaction from the corresponding substituted (2-bromophenoxy)-acetic acid chlorides2 and imine5.

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Heteroüberbrückte tricyclische -Lactame: Ein einfacher Zugang zu 1,2,2a,8a-Tetrahydro-3-oxa-1-aza-cyclobuta[b]naphthalin-2-onen

Zusammenfassung Die cis-substituierten 3-(2-Bromaryloxy)-azetidin-2-one6, dargestellt durch stereospezifische Säurechlorid/Imin-Reaktion aus den entsprechenden (2-Brom-phenoxy)-acetylchloriden2 und den Iminen5, reagieren im Zuge einer intramolekularen radikalischenexo-trig-Reaktion zu den 3,4-heteroüberbrückten tricyclischen -Lactamen7 und8.

     

Silylenolether-Funktionalisierung, 3. Mitt. Regioselektive Acylierung von Trimethylsilylenolethern mit 2-Alkoxy-1,3-dioxolanen — Synthese von α- und γ-geschützten Dicarbonylverbindungen

Acylation of silylenol ethers1 and9 yield with 2-alkoxy-2-alkyl(or aryl)-1,3-dioxolanes5 in a simple way by zinc dichloride-diethyl ether-catalysis regioselectively the - and -protected dicarbonyl derivatives6,7, and10. The enhanced reactivity of the cyclic orthoesters5 in this reaction is discussed in comparison with acyclic reagents. The yield is influenced by steric effects at the reaction center.

     

Zur gezielten Oxidation der Δ7-Doppelbindung in den 4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten des Vitamin D3

The possibility of regio- and stereospecific oxidation of the 7-double bond of the 4-phenyl-1,2,4-triazolin-3,5-dione adducts1 a and1 b of Vitamin D₃ is reported. Oxidation of the corresponding benzoates2 a and2 b withm-Chlorperbenzoic acid yields the two oxirans3 a and3 b which in turn with NaI-CH₃COOH-Zn after saponification to5 a and5 b lead to the allylic alcohols6 a and6 b.

     

Strukturelle Abwandlungen an N-Acetylneuraminsäure, 25. Mitt.: Synthese von Methyl-2-α-glycosiden von 4-epi-, 7-epi-, 8-epi- und 7,8-bis-epi-N-Acetylneuraminsäure

The -methylketoside of N-acetylneuraminic acid methylester (4) is transformed via the deacetylated compound5 into the 9,8-O-isopropylidenderivative6 which could be oxidized regioselectively by RuO₄ to the corresponding 4-oxo-sialic acid analogue7. Reduction with the boraneammonia complex produces a 1:1 mixture of6 and the desired -methylketoside of 9,8-O-isopropyliden-4-epi-N-acetyl-neuraminic acid methylester (8). Removing of the isopropylidene group gives the -methylketoside of 4-epi-N-acetylneuraminic acid methylester (9), which was further transformed to the ammonium salt of 4-epi-N-acetylneuraminic acid -methylketoside (10). On the other hand compound5 was turned into the 4,8,9-tri-O-t-butyldimethylsilylderivative11 a from which the corresponding 7-oxo-compound12 by oxidation with RuO₄ derives. The reduction of12 with BH₃ - NH₃ yielded a 1:1 mixture of the starting material11 a and the desired 7-epi-derivative13 a which gives either via the purified peracetylated -methylketosid of 7-epi-N-acetylneuraminic acid methylester (14) or a direct saponification the sodium salt of 7-epi-N-acetylneuraminic acid--methylketoside (15).Applying the Königs-Knorr procedure to the peracetylated 8-epi-N-acetylneuraminic acid methylester (16) gives rise to the formation of a 1:1 mixture of the corresponding - and -methylketosides17 and18 besides traces of the corresponding 2,3-dideoxy-2,3-dideohydro-sialic acid derivative19. After chromatographic separation of17 further saponification leads to the sodium salt of 8-epi-N-acetylneuraminic acid--methylketoside (20). In an analogous procedure the sodium salt of 7,8-di-epi-N-acetylneuraminic acid--methylketoside (25) was prepared starting from the peracetylated 7,8-di-epi-N-acetylneuraminic acid methylester (21), whereby a mixture of the - and -methylketosides22 and23 was formed in a ratio 95:5 besides traces of the peracetylated 2,3-dideoxy-2,3-didehydrosialic acid methylester (24).

On study leave from the Department of Chemistry, Postgraduate and Research Center, R.B.N.B. College, Shrirampur-413709 (MS), India     

Transformationen von β-Glycofuranosylisocyaniden in Tetrahydrofuranderivate

Summary Readily available -glycofuranosyl isocyanides1,2,4,5,6,18,19,20 are transformed into the corresponding protected tetrahydrofurans21,22,23,24,25,26 by means of tributyltin hydride andAIBN. The synthesis of18 and19 by dehydration of the formamide15 is described. Starting with 6-deoxy-1,2-O-isopropyliden--D-allofuranose (7) crystalline 1,2-O-diacetyl-3,5-dibenzoyl--D-allofuranose (9) is obtained.9 is first transformed into the anomeric azides11,12 and13,14 and subsequently into the formamide15.

     

Aromatische Spirane, 17. Mitt.: Darstellung von anellierten und substituierten 2,2′-Spirobiindan-1-onen und 4,5′-disubstituierten 2,2′-Spirobiindanen

Summary The spiroketones9, 16, and28 were prepared by cyclisation of the carboxylic acids7c, 13b, and25c and their acid chlorides, resp. (7d, 13c, and25d) with polyphosphoric acid (PPA) or SnCl₄. The precursors of the latter compounds were synthesized by alkylation of the appropriate -ketoester1 or2 with the benzylchlorides3 or4 with NaH inDMF. Subsequent hydrogenation with Pd/C led to the desired alkylated indane-esters. The chiral compounds11, 17, and31 were obtained by Friedel-Crafts acetylation. The chiral disubstituted 2,2-Spirobiindanes22 and36 were prepared from the ketones20 and32/33 by catalytic reduction followed by Friedel-Crafts acetylation.

     

Diborane as a reducing agent IX: Reduction of aTris(trifluoroacetyl)enaminospiroindoline

Summary Reduction of the title compound (2) with diborane furnishes 1-trifluoroethyl-3-(2-(trifluoroethylamino)ethyl)-3-vinylindoline (4), 1-hydroxy-trifluoroethyl-3-(2-(trifluoroethylamino)ethyl)indole (5), and 1-methyl-2-trifluoroethyl-1,2,3,4-tetrahydro--carboline (6). However, treatment of2 with lithium aluminum hydride, H₂/Pd on charcoal, and sodium borohydride affords hydroxyspiroindolenine8, hydroxy-bis(trifluoroacetyl)enaminospiroindoline9, andN-ethyltryptamine7, respectively. The results are discussed and the mechanisms of the reactions leading to4–8 are presented.

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Diboran als Reduktionsmittel, 9. Mitt.: Reduktion einesTris(trifluoroacetyl)enaminospiroindolins

Zusammenfassung Reduktion der Titelverbindung (2) mit Diboran ergibt 1-Trifluoroethyl-3-(2-(trifluoroethylamino)ethyl)-3-vinylindolin (4), 1-Hydroxy-trifluoroethyl-3-(2-(trifluoroethylamino)ethyl)indol (5) und 1-Methyl-2-trifluoroethyl-1,2,3,4-tetrahydro--carbolin (6). Behandlung von2 mit Lithiumaluminiumhydrid, H₂/Pd auf Aktivkohle und Natriumborhydrid führt jedoch zu Hydroxyspiroindolenin8, Hydroxy-bis(trifluoroacetyl)enaminospiroindolin9 und N-Ethyltryptamin (7). Die Ergebnisse werden diskutiert und die Mechanismen der zu den Produkten4–8 führenden Reaktionen werden vorgestellt.

     

Strukturelle Abwandlungen anN-Acetylneuraminsäure, 3

From methyl-5-acetylamino-7,8-anhydro-4,9-O-bis-(t-butyldimethylsilyl)-3,5-dideoxy--D-glycero-D-galacto-2-nonulopyranosidonic acid methylester (1) the derivatives1 a and1 b were obtained by removing the 9-O-(t-butyldimethylsilyl)group withBu ₄NF, followed by acetylation. Treatment of1 b with 80% acetic acid and acetanhydride/pyridine yields the 8-epi-N-acetylneuraminic acid derivative2 a and the 7-epi-N-acetylneuraminic acid derivative3 a in a ratio of 3:1 (Scheme 1). The structure elucidation of2 b was achieved by converting2 b via the 4,9-bis-O-(tBDMSi)-8-O-tosyl-derivative2 d into the epoxide1 (Scheme 2). Using the same sequence the epoxides4 and5 were transformed into theN-acetylneuraminic acid derivative6 a and the 7,8-bis-epi-N-acetylneuraminic acid derivative7 a (Scheme 3). After treatment with sodium hydroxide and 0.025m HCl and Dowex 50 H⁺ the 8-epi-, 7-epi- and 7,8-bis-epi-N-acetylneuraminic acids2,3, and7 were obtained. These three compounds were tested withCMP-N-acetylneuraminic acid synthetase.

Herrn KollegenK. Schlögl mit den besten Wünschen zum 60. Geburtstag.     

Glykosylazide als Ausgangsbasis zur Gewinnung von Nucleosidanalogen, 3. Mitt. Synthese von Alkylaminotetrazol- und Uretidinonnucleosiden

The -ribofuranosylazide1 is transformed after usual derivatization by suitable protecting groups into the P–N-ylid2, which gives the corresponding N-Glykosyl-N-alkylcarbodiimides4 and a small amount of the glykosylisocyanatde-rivative3 by reaction with alkylisocyanates. The carbodiimides4 were reacted with hydrazoic acid to give the alkylaminotetrazolnucleosides5 and finally the free nucleosidanalogs6. In the case of5 c the 5-aziridinyltetrazolnucleosid5 h was formed by an usual neighbouring group reaction. In addition the compound1 is transformed into the 3,5-diprotected anchor derivative7 by reaction withTIPSCl₂. The latter could be transformed by usual steps into the alkylaminotetra-zolnucleosides8 with a free 2-OH group. In the next step the 2-p-tolylthiocarbo-nates9 were prepared followed by transformation to the 2-desoxynucleosides10 by means of tributyltinhydride. Finally the free 2-desoxynucleosides11 were prepared. By reacting the carbodiimides4 with phenylisocyanate a mixture of the two possible regiouretidinonnucleosidderivatives12 and13 are formed. In the case of the N-glykosyl-N-allylcarbodiimide4 d only the one isomer13 d arises.

Herrn Prof. Dr.A. Neckel mit den besten Wünschen zum 60. Geburtstag gewidmet.