Stereoselectivity of the annelation of 3,4-dihydroisoquinolines by 5-monosubstituted 2-acylcyclohexane-1,3-diones

Gulyakevich, O. V.; Rubinova, I. L.; Rubinov, D. B.; Govorova, A. A.; Lyakhov, Alexander S.; Михальчук, А. Л.

doi:10.1070/mc1999v009n03abeh001065

Cited by 5 publications

(6 citation statements)

References 6 publications

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“…Conformer 2b is favored over conformer 2a in the 2a-2b conformer pair and, hence, is probably more populated. This result is in good accord with the X-ray structural data obtained for related 12,17a-diketo derivatives [13,14], which indicate that 8-aza-D-homogona-12,17a-dione molecules in all cases studied have cis fusion of rings B and C and α-configuration of C (16) .…”

supporting

confidence: 93%

“…In turn, C (10) does not have cross peaks with the protons at C (1) and C (7) but signals are observed with protons at C (11) . C (13) has cross peaks with C (11) βHa, C (17a) αH, C (17) βH, and a strong signal with C (11) αHe, which additionally indicates an equatorial position of this proton. C (14) has cross peak with protons at C (15) and C (7) and the signal of C (7) βHe is stronger, as expected considering its equatorial position (angle close to 0).…”

mentioning

confidence: 95%

“…Thus, the signals for C (11) αH and C (1) H were shifted upfield by 0.31 and 0.08 ppm, respectively, while the intensity of the outer lines in the AB system of the protons at C (15) (the chemical shift-coupling constant ratio was 1.5). The 13 C NMR spectrum shows shifts for C (12) and C (13) downfield by 14.5 and 2.1 ppm, respectively, and for C (17a) upfield by 2 ppm.…”

mentioning

confidence: 97%

“…The long-wavelength band, according to our previous work [9], should be assigned to the trans-s-trans N (8) -C (14) =C (13) -C (17a) =O chromophore, while the short-wavelength band should be assigned to the aromatic chromophore (ring A).…”

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confidence: 99%

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Synthesis and structure of 12-hydroxyimino derivatives of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10), 13-tetraene-12,17a-dione

Михальчук

Gulyakevich

Baranovskii

et al. 2007

Chem Heterocycl Compd

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Keywords: 8-aza-D-homogona-12,17a-diones, 12-hydroxyimino derivatives of 1-aza-D-homogona-12,17a-diones, syn-anti isomerism, quantum-mechanical analysis, IR, UV, 1 H NMR, and 13 C NMR spectroscopy, COSY, NOESY, HMBC, HMQC.Studies of the biological properties of 8-azasteroids, in particular, 8-azagona-12,17-diones [1] and 8-aza-D-homogona-12,17a-diones [1-6], have shown that these compounds have immunomodulating properties, affecting the immune systems of higher mammals and humans [2, 3, 6]. Furthermore, Kuz'mitskii et al. [2][3][4] have found that, depending on their structure, these compounds may act as either activators or suppressors of the immune response. This has led us to try to explain the role of structural factors in the direction and level of the observed immunological activity. We have found that oxyimino derivatives of 8-aza-D-homogona-12,17a-diones also display immunological activity [7].In this communication, we present syntheses for 12-hydroxy (2) and 12-methoxy derivatives (3) of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10),13-tetraene-12,17a-dione (1) and the results of IR, UV, and NMR studies to elucidate the steric structure and molecular dynamics of these compounds.The reaction of 8-aza-D-12,17a-dione 1 with hydroxylamine and methoxylamine in ethanol gave 12-oximino derivatives of 8-aza-D-homogonane 2 and 3. Alternatively, 12-oximino derivative 2 was obtained by the reaction of 1 with hydroxylamine hydrochloride with subsequent cleavage of the resultant salt 4 by such bases as NaOH or NaOMe. 12-Methoxyimino derivative 3 was also obtained by the methylation of hydroxyimino derivative 2 using methyl iodide in the presence of sodium methylate. Physicochemical data were obtained for all these compounds, which permit reliable assignment of their structures. __________________________________________________________________________________________

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supporting

confidence: 93%

mentioning

confidence: 95%

mentioning

confidence: 97%

mentioning

confidence: 99%

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Synthesis and structure of 12-hydroxyimino derivatives of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10), 13-tetraene-12,17a-dione

Михальчук

Gulyakevich

Baranovskii

et al. 2007

Chem Heterocycl Compd

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“…The change in the planarity of the AAVC moiety when a methyl group is introduced into the position 11 may be explained by stereoelectronic effects involving interaction of the group with the π-electrons of the aromatic ring A. This conclusion is quite consistent with X-ray diffraction data for 8-aza steroids [28] and the results of examination of Dreiding models for compounds 4a-d, which shows that due to bending of the molecular frameworks at the N (8) -C (9) bond, the 11-Me group is found in a region of anisotropy of the π-electron cloud of ring A.…”

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confidence: 82%

Annelation of 3,4-dihydroisoquinolines by 3-acyl-5,5-dimethylthiopyran-2,4-diones. Synthesis and properties of 8-aza-17-thia-d-homogona-12,17a-diones

Budnikova

Gulyakevich

Zheldakova

et al. 2004

Chem Heterocycl Compd

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Among heterocyclic analogs of steroids, the most well known today are the aza analogs, in particular those exhibiting quite valuable properties as inhibitors of 5α-reductase and antiandrogens, 4-aza steroids [1,2], and also 8-aza steroids, which are of considerable practical and theoretical interest as low molecular weight immunomodulators [3][4][5]. Studies of the structure-function relations in the 8-aza steroid series have shown [3,[5][6][7]] that by means of structural and functional group transformations, we can change both the direction and the level of their immunomodulating effect. A quite promising approach to controlling the immune activity of 8-aza steroids is to introduce additional heteroatoms into their tetracyclic ring [8]. So far 8,16-diaza-[9], 8-aza-16-oxa-[10], 8-aza-16-thia- [11], 8,17-diaza-D-homo-[12], and 8-aza-17-oxa-D-homogonanes have been synthesized and studied [13]. At the same time, compounds in the 8-aza-17-thia-D-homogonane series have been described only recently [14]. With the aim of expanding the indicated series, we have studied the reaction of 3,4-dihydroisoquinolines 1a-d with 3-acyl-6,6-dimethylthiopyran-2,4-diones 2a,b, obtained from 6,6-dimethyltetrahydrothiopyran-2,4-dione (3). In this case, it was also important to clarify the effect of the sulfur atom in the ring of the original dione 2 on the activity of the latter in the reaction with compounds 1. We have established that when 3,4-dihydroisoquinolines 1a,b, unsubstituted in the 1 position, are boiled in ethanol with diones 2a,b, the corresponding tetracyclic derivatives 4a-d are formed: the products of an annelation reaction ([2+4] cyclocondensation) at the C=N bond (Scheme 1). However, we were unable to obtain products of type 3 from 1-methyl-substituted dihydroisoquinolines 1c,d and the same diones 2a,b. The data presented

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Reactions of Aldehydes and Ketones and Their Derivatives

Murray¹

Organic Reaction Mechanisms• 1999

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Stereoselectivity of the annelation of 3,4-dihydroisoquinolines by 5-monosubstituted 2-acylcyclohexane-1,3-diones

Cited by 5 publications

References 6 publications

Synthesis and structure of 12-hydroxyimino derivatives of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10), 13-tetraene-12,17a-dione

Synthesis and structure of 12-hydroxyimino derivatives of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10), 13-tetraene-12,17a-dione

Annelation of 3,4-dihydroisoquinolines by 3-acyl-5,5-dimethylthiopyran-2,4-diones. Synthesis and properties of 8-aza-17-thia-d-homogona-12,17a-diones

Reactions of Aldehydes and Ketones and Their Derivatives

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