Synthesis of aza steroid analogs

Aleksandrov, B. B.; Shklyaev, V. S.; Shklyaev, Yu. V.

doi:10.1007/bf00472532

Cited by 3 publications

(8 citation statements)

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“…In a compound of the 56 type with a 1-ethoxycarbonyl group (R 1 = COOEt, R 2 = H) under analogous conditions the latter takes part, together with the C (2) =O group [16,50,52], in reaction with hydrazine hydrate, and the product 59 is formed [51]. …”

Section: Reactions With Hydrazines and Hydroxylaminementioning

confidence: 97%

“…Substituted tetrahydropyrrolo[1,2-a]isoquinoline-2,3-diones of type 56 [12,17,23,52] and their benzannelated analogs 83 [16,27,60] react with triallylborane at the C (2) =O group with the formation of the corresponding unsaturated alcohols 84 and 85 [60] …”

Section: Allylboronation Reactionsmentioning

confidence: 99%

“…The reaction of substituted 5,5-dimethyltetrahydropyrrolo[1,2-a]isoquinolinediones 56 [16,50,52] with hydrazine hydrate, N,N-dimethylhydrazine, phenylhydrazine, semicarbazide, and thiosemicarbazide boiled in ethanol takes place at the C (2) =O group with the formation of the corresponding derivatives 57 or (with favorable structural factors) 58 with an intramolecular hydrogen bond [50,51]. In a compound of the 56 type with a 1-ethoxycarbonyl group (R 1 = COOEt, R 2 = H) under analogous conditions the latter takes part, together with the C (2) =O group [16,50,52], in reaction with hydrazine hydrate, and the product 59 is formed [51].…”

Section: Reactions With Hydrazines and Hydroxylaminementioning

confidence: 99%

“…The reaction of the N-substituted amide 3 with one mole of oxalyl chloride leads to the product from dehydration and closure of the 1,3-dioxazine ring, i.e., the enamine 4, which is acylated by a second molecule of oxalyl chloride with the formation of a derivative of pyrrolo[2,1-b][1,3]oxazinetrione 5 [21]. + -During treatment with oxalyl chloride 1-chloromethyl-and 1-methyl-6,7-dimethoxy-3,4,6,7-tetrahydroisoquinolines 6 [14], the substituted tetrahydro derivatives 7 of isoquinolines (n = 1) [7, 9, 11, 17-19, 22, 23] and 5H-benzo[c]azepines (n = 2) [24][25][26][27], the cyclohexaannelated tetrahydroisoquinolines 8 [28] and the dihydroisoquinolines 9 [16], and tetrahydrofuro [3,2-c]pyridine [29] form the corresponding 2,3-dihydro-2,3-pyrrolediones annelated with the azaheterocycles on the [a] side with good yields (57-82% …”

mentioning

confidence: 99%

“…The reaction is usually conducted in an inert aprotic solvent (ether [7,[9][10][11], chloroform [9,12], dichloromethane [13], 1,2-dimethoxyethane [14], benzene [15,16], dioxane [17]) or in pyridine in the range of 0-100°C for 1.5-3.5 h. The yields of the desired products are as a rule good particularly if the enamine contains at least one electron-withdrawing substituent (a COR or COOR group); there has been are no mention of the isolation of side products.…”

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confidence: 99%

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Synthesis and chemical transformations of 2,3-dihydropyrrole-2,3-diones annelated on the [a] side by azaheterocycles. (Review)

Mashevskaya

Масливец

2006

Chem Heterocycl Compd

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Data on methods for the synthesis of 2,3-dihydro-2,3-pyrrolediones condensed with azaheterocycles on the [a] side are reviewed. Their reactions with nucleophilic reagents, allylboronation, reduction, and thermal transformations are discussed.The chemistry of 2,3-dihydro-2,3-pyrrolediones condensed with azaheterocycles on the [a] side first evolved in the seventies, when the application of 2,3-dihydro-2,3-pyrroledione derivatives as synthetic blocks for the construction of alkaloid molecules was first demonstrated [1][2][3][4][5][6][7].It should be mentioned that up to the beginning of the nineties these annelated dihydropyrrolediones were studied almost exclusively as subjects for photoreduction and photocyclization or as dienophiles in DielsAlder reactions (for the production of intermediate compounds in the synthesis of alkaloids). A large part of these papers belong to certain groups of investigators [1][2][3][4][5]. Single reports on reactions with nucleophilic reagents, allylboronation, reduction, and thermal transformations of 2,3-dihydro-2,3-pyrrolediones annelated with azaheterocycles on the [a] side have only begun to appear comparatively recently. This region of their chemical behavior has been studied little in spite of the fact that they exhibit high reactivity toward various nucleophiles (particularly with the presence of several electron-withdrawing substituents in the rings) and generate imidoylketenes during thermolysis.In the present review we examine publications existing up to March, 2002, on methods for the production of dihydropyrrolediones condensed with azaheterocycles and their chemical transformations. The review does not include data on the chemistry of isatins and their aza analogs, which were described in [8], or data on the cycloaddition of these pyrrolediones, which have been discussed before [1][2][3][4][5][6][7][9][10][11] and were reviewed in [11].

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Section: Reactions With Hydrazines and Hydroxylaminementioning

confidence: 97%

Section: Allylboronation Reactionsmentioning

confidence: 99%

Section: Reactions With Hydrazines and Hydroxylaminementioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

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Synthesis and chemical transformations of 2,3-dihydropyrrole-2,3-diones annelated on the [a] side by azaheterocycles. (Review)

Mashevskaya

Масливец

2006

Chem Heterocycl Compd

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Enamines of the 1,2,3,4-tetrahydroiso-quinoline series in the Chichibabin synthesis of pyrrolo[2,1-a]isoquinolines and in reaction with oxalyl chloride

Polygalova

Михайловский

Vikhareva

et al. 2007

Chem Heterocycl Compd

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Pyrrolo[2,1-a]isoquinolines are used widely in organic synthesis, medicine, and other areas [1]. The classical method of design the pyrrolo[2,1-a]isoquinoline system is the interaction of 1-alkylisoquinolines with α-halo ketones (the Chichibabin reaction) [1,2]. It is known [3] that on cyclization with the formation of condensed systems a determining role is played by the radicals in position 3 of the isoquinoline ring. The aim of the present work is an investigation of the potentialities of this reaction in the presence of two methyl groups in position 3 and also of a different structure for the enamine fragment.The reaction of enamines of the 1,2,3,4-tetrahydroisoquinoline series with oxalyl chloride has also been widely investigated [1,4,5]. In the given examples, both bases, in the molecules of which the structure of the enamine is already fixed, and compounds in the imino form, enter into this reaction. The latter is characteristic for derivatives of 1-alkylisoquinoline [6,7], the alkyl residue in the structure of which, unlike carbonyl or just withdrawing groups, does not aid stabilization of the enamine form. Consequently our aim is the study of the conditions of carrying out and the structures of the products of the named reaction in the presence of an alkyl residue at position 1 of the isoquinoline ring.The investigations showed that the reaction of enamines 1a-c with p-bromophenacyl bromide proceeds readily on boiling in alcohol in the presence of Na 2 CO 3 and compounds 2a-c are formed. On using drotaverine (no-spa) base as the initial enamine the reaction product is compound 2d. Enamino amides and enamino esters of the benzo[f]isoquinoline series, analogous in structure to compounds 1a-c, form the corresponding tetracyclic derivatives 3a-c in this reaction. __________________________________________________________________________________________ Perm State Pharmaceutical Academy,

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Synthesis of 2-(3-coumarinyl)pyrrolo[2,1-a]isoquinoline derivatives by the chichibabin reaction

Kulikova

Сурикова

Михайловский

et al. 2011

Chem Heterocycl Comp

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Keywords: benzo[f]isoquinoline, benzo[f]coumarin, 3-bromoacetylcoumarin, enamines of the 3,3-dimethyl-1,2,3,4-tetrahydroisoquinoline series, 2-(3-coumarinyl)-5,5-dimethyl-5,6-dihydropyrrolo[2,1-a]-isoquinolines, Chichibabin reaction.The classical method for the construction of the pyrrolo[2,1-a]isoquinoline system is the Chichibabin reaction, which involves the reaction of 1-methylisoquinoline with α-halo ketones [1, 2]. The successful use not only of heteroaromatic compounds such as pyridines and their benzo analogs but also of cyclic enamine derivatives in this reaction is well known [2,3]. Here 3-bromoacetylcoumarins are also worthy of attention as α-halo ketones in so far as the formation of a system consisting of two independent heterocyclic fragmentspyrrolo[2,1-a]isoquinoline and coumarin -has been proposed in this case. Structures of such a type are practically unknown in the literature. The aim of the present work was to investigate the possibilities of annelation of the pyrrole ring depending on the structure of the initial reagents.The investigations showed that the reaction of the isoquinoline 1 with 3-bromoacetylcoumarin takes place readily with boiling in 2-propanol in the presence of Na 2 CO 3 , with the formation of compound 2. If compounds 3a,b are used as initial enamines the reaction products are compounds 4a,b. The corresponding bromoacetyl derivative of benzo[f]coumarin gives compound 5a in reaction with the enamine 1 and the amide 5b in reaction with the enamino amide 3b. In reaction with 3-bromoacetylcoumarin the benzo[f]isoquinoline derivative 6 forms the tetracyclic system 7. The obtained coumarin derivatives 2, 4, 5, and 7 (Table 1) are yellow crystalline substances.In the 1 H NMR spectra of the synthesized compounds (Table 2), in contrast to the spectra of the initial enamines, there are singlets for the pyrrole ring (6.28-7.12 ppm), the shift of which depends on the substituent at position 1 of the pyrrolo[2,1-a]isoquinoline system. All the spectra contain singlets for the HC= group of the coumarin ring (7.80-8.56 ppm) [4].

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Synthesis of aza steroid analogs

Cited by 3 publications

References 1 publication

Synthesis and chemical transformations of 2,3-dihydropyrrole-2,3-diones annelated on the [a] side by azaheterocycles. (Review)

Synthesis and chemical transformations of 2,3-dihydropyrrole-2,3-diones annelated on the [a] side by azaheterocycles. (Review)

Enamines of the 1,2,3,4-tetrahydroiso-quinoline series in the Chichibabin synthesis of pyrrolo[2,1-a]isoquinolines and in reaction with oxalyl chloride

Synthesis of 2-(3-coumarinyl)pyrrolo[2,1-a]isoquinoline derivatives by the chichibabin reaction

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