TY  - JOUR
AU  - Milić, Dragana
AU  - Kop, Tatjana
AU  - Juranić, Z.
AU  - Gasic, MJ
AU  - Tinant, B
AU  - Pocsfalvi, G
AU  - Šolaja, Bogdan A.
PY  - 2005
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/748
AB  - A simple approach to aromatization of steroidal quinols and epoxyquinols using a catalytic amount of TMSOTf is reported. Beside acetylation of the angular OH, the acid-catalyzed (TfOH) dienone-phenol rearrangement occurred affording "para" products, or in the case of blocked position 4, the acetoxy group 1,2-migration leads to the formation of "meta" products. Using epoxyquinol derivative as a substrate, the acetoxy group elimination was observed, followed by acid-catalyzed epoxy-ring opening and subsequent double bond migration, giving as a final product Delta(9,11) A-ring aromatized compounds. Synthesis of conduritol-like compounds and structure confirmation by X-ray crystallography of the precursor of steroidal conduritol is also described. In addition, the results of extensive antiproliferative screening against a panel of 60 cancer cell lines are presented. (c) 2005 Elsevier Inc. All rights reserved.
PB  - Elsevier Science Inc, New York
T2  - Steroids
T1  - Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds
VL  - 70
IS  - 14
SP  - 922
EP  - 932
DO  - 10.1016/j.steroids.2005.07.001
ER  - 

@article{
author = "Milić, Dragana and Kop, Tatjana and Juranić, Z. and Gasic, MJ and Tinant, B and Pocsfalvi, G and Šolaja, Bogdan A.",
year = "2005",
abstract = "A simple approach to aromatization of steroidal quinols and epoxyquinols using a catalytic amount of TMSOTf is reported. Beside acetylation of the angular OH, the acid-catalyzed (TfOH) dienone-phenol rearrangement occurred affording "para" products, or in the case of blocked position 4, the acetoxy group 1,2-migration leads to the formation of "meta" products. Using epoxyquinol derivative as a substrate, the acetoxy group elimination was observed, followed by acid-catalyzed epoxy-ring opening and subsequent double bond migration, giving as a final product Delta(9,11) A-ring aromatized compounds. Synthesis of conduritol-like compounds and structure confirmation by X-ray crystallography of the precursor of steroidal conduritol is also described. In addition, the results of extensive antiproliferative screening against a panel of 60 cancer cell lines are presented. (c) 2005 Elsevier Inc. All rights reserved.",
publisher = "Elsevier Science Inc, New York",
journal = "Steroids",
title = "Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds",
volume = "70",
number = "14",
pages = "922-932",
doi = "10.1016/j.steroids.2005.07.001"
}

Milić, D., Kop, T., Juranić, Z., Gasic, M., Tinant, B., Pocsfalvi, G.,& Šolaja, B. A.. (2005). Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds. in Steroids
Elsevier Science Inc, New York., 70(14), 922-932.
https://doi.org/10.1016/j.steroids.2005.07.001

Milić D, Kop T, Juranić Z, Gasic M, Tinant B, Pocsfalvi G, Šolaja BA. Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds. in Steroids. 2005;70(14):922-932.
doi:10.1016/j.steroids.2005.07.001 .

Milić, Dragana, Kop, Tatjana, Juranić, Z., Gasic, MJ, Tinant, B, Pocsfalvi, G, Šolaja, Bogdan A., "Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds" in Steroids, 70, no. 14 (2005):922-932,
https://doi.org/10.1016/j.steroids.2005.07.001 . .

TY  - JOUR
AU  - Šolaja, Bogdan A.
AU  - Terzić-Jovanović, Nataša
AU  - Pocsfalvi, G
AU  - Gerena, L
AU  - Tinant, B
AU  - Opsenica, Dejan M.
AU  - Milhous, WK
PY  - 2002
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/500
AB  - Mixed 1,2,4,5-tetraoxanes possessing simple spirocycloalkane and spirocholic acid-derived substituents were prepared and shown to have significantly higher in vitro antimalarial activity than bis-substituted tetraoxanes. Out of 41 synthesized tetraoxanes, 12 were in vitro more potent against Plasmodium falciparum chloroquine-resistant W2 clone than artemisinin, and the most potent one was 2.4 times as active as arteether. In addition, 9 compounds exhibit higher activity than chloroquine against P. falciparum chloroquine-susceptible D6 clone. Cytotoxicity was assessed for most active compounds against the Vero cell line, showing a cytotoxicity/antimalarial potency ratio of 1/(1400-9500). For the first time, tetraoxanes were screened against Mycobacterium tuberculosis with MICs as low as 4.73 muM against H37Rv strain. Mixed tetraoxanes were synthesized in a simple procedure from cholic acid methyl esters by direct coupling of steroidal gem-dihydroperoxide to simple ketones and further transformed into corresponding acids and amides.
PB  - Amer Chemical Soc, Washington
T2  - Journal of Medicinal Chemistry
T1  - Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity
VL  - 45
IS  - 16
SP  - 3331
EP  - 3336
DO  - 10.1021/jm020891g
ER  - 

@article{
author = "Šolaja, Bogdan A. and Terzić-Jovanović, Nataša and Pocsfalvi, G and Gerena, L and Tinant, B and Opsenica, Dejan M. and Milhous, WK",
year = "2002",
abstract = "Mixed 1,2,4,5-tetraoxanes possessing simple spirocycloalkane and spirocholic acid-derived substituents were prepared and shown to have significantly higher in vitro antimalarial activity than bis-substituted tetraoxanes. Out of 41 synthesized tetraoxanes, 12 were in vitro more potent against Plasmodium falciparum chloroquine-resistant W2 clone than artemisinin, and the most potent one was 2.4 times as active as arteether. In addition, 9 compounds exhibit higher activity than chloroquine against P. falciparum chloroquine-susceptible D6 clone. Cytotoxicity was assessed for most active compounds against the Vero cell line, showing a cytotoxicity/antimalarial potency ratio of 1/(1400-9500). For the first time, tetraoxanes were screened against Mycobacterium tuberculosis with MICs as low as 4.73 muM against H37Rv strain. Mixed tetraoxanes were synthesized in a simple procedure from cholic acid methyl esters by direct coupling of steroidal gem-dihydroperoxide to simple ketones and further transformed into corresponding acids and amides.",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of Medicinal Chemistry",
title = "Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity",
volume = "45",
number = "16",
pages = "3331-3336",
doi = "10.1021/jm020891g"
}

Šolaja, B. A., Terzić-Jovanović, N., Pocsfalvi, G., Gerena, L., Tinant, B., Opsenica, D. M.,& Milhous, W.. (2002). Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity. in Journal of Medicinal Chemistry
Amer Chemical Soc, Washington., 45(16), 3331-3336.
https://doi.org/10.1021/jm020891g

Šolaja BA, Terzić-Jovanović N, Pocsfalvi G, Gerena L, Tinant B, Opsenica DM, Milhous W. Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity. in Journal of Medicinal Chemistry. 2002;45(16):3331-3336.
doi:10.1021/jm020891g .

Šolaja, Bogdan A., Terzić-Jovanović, Nataša, Pocsfalvi, G, Gerena, L, Tinant, B, Opsenica, Dejan M., Milhous, WK, "Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity" in Journal of Medicinal Chemistry, 45, no. 16 (2002):3331-3336,
https://doi.org/10.1021/jm020891g . .

TY  - JOUR
AU  - Opsenica, Dejan M.
AU  - Pocsfalvi, G
AU  - Juranić, Z.
AU  - Tinant, B
AU  - Declercq, JP
AU  - Kyle, DE
AU  - Milhous, WK
AU  - Šolaja, Bogdan A.
PY  - 2000
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/441
AB  - Cholic acid-derived 1,2,4,5-tetraoxanes were synthesized in order to explore the influence of steroid carrier on its antimalarial and antiproliferative activity in vitro. Starting with chiral ketones, cis and trans series of diastereomeric tetraoxanes were obtained, and the cis series was found to be similar to 2 times as active as the trans against Plasmodium falciparum DG and W2 clones. The same tendency was observed against human melanoma (Fem-X) and human cervix carcinoma (HeLa) cell lines. The amide C(24) termini, for the first time introduced into the carrier molecule of a tetraoxane pharmacophore, significantly enhanced both antimalarial and antiproliferative activity, as compared to the corresponding methyl esters, with cis-bis(N-propylamide) being most efficient against the chloroquine-susceptible D6 clone (IC50 = 9.29 nM). cis- and trans-bis(N-propylamides) were also screened against PBMC, and PRA-stimulated PBMC, showing a cytotoxicity/antimalarial potency ratio of 1/10 000.
PB  - Amer Chemical Soc, Washington
T2  - Journal of Medicinal Chemistry
T1  - Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: Structure and antimalarial and antiproliferative activity
VL  - 43
IS  - 17
SP  - 3274
EP  - 3282
DO  - 10.1021/jm000952f
ER  - 

@article{
author = "Opsenica, Dejan M. and Pocsfalvi, G and Juranić, Z. and Tinant, B and Declercq, JP and Kyle, DE and Milhous, WK and Šolaja, Bogdan A.",
year = "2000",
abstract = "Cholic acid-derived 1,2,4,5-tetraoxanes were synthesized in order to explore the influence of steroid carrier on its antimalarial and antiproliferative activity in vitro. Starting with chiral ketones, cis and trans series of diastereomeric tetraoxanes were obtained, and the cis series was found to be similar to 2 times as active as the trans against Plasmodium falciparum DG and W2 clones. The same tendency was observed against human melanoma (Fem-X) and human cervix carcinoma (HeLa) cell lines. The amide C(24) termini, for the first time introduced into the carrier molecule of a tetraoxane pharmacophore, significantly enhanced both antimalarial and antiproliferative activity, as compared to the corresponding methyl esters, with cis-bis(N-propylamide) being most efficient against the chloroquine-susceptible D6 clone (IC50 = 9.29 nM). cis- and trans-bis(N-propylamides) were also screened against PBMC, and PRA-stimulated PBMC, showing a cytotoxicity/antimalarial potency ratio of 1/10 000.",
publisher = "Amer Chemical Soc, Washington",
journal = "Journal of Medicinal Chemistry",
title = "Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: Structure and antimalarial and antiproliferative activity",
volume = "43",
number = "17",
pages = "3274-3282",
doi = "10.1021/jm000952f"
}

Opsenica, D. M., Pocsfalvi, G., Juranić, Z., Tinant, B., Declercq, J., Kyle, D., Milhous, W.,& Šolaja, B. A.. (2000). Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: Structure and antimalarial and antiproliferative activity. in Journal of Medicinal Chemistry
Amer Chemical Soc, Washington., 43(17), 3274-3282.
https://doi.org/10.1021/jm000952f

Opsenica DM, Pocsfalvi G, Juranić Z, Tinant B, Declercq J, Kyle D, Milhous W, Šolaja BA. Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: Structure and antimalarial and antiproliferative activity. in Journal of Medicinal Chemistry. 2000;43(17):3274-3282.
doi:10.1021/jm000952f .

Opsenica, Dejan M., Pocsfalvi, G, Juranić, Z., Tinant, B, Declercq, JP, Kyle, DE, Milhous, WK, Šolaja, Bogdan A., "Cholic acid derivatives as 1,2,4,5-tetraoxane carriers: Structure and antimalarial and antiproliferative activity" in Journal of Medicinal Chemistry, 43, no. 17 (2000):3274-3282,
https://doi.org/10.1021/jm000952f . .

TY  - JOUR
AU  - Šolaja, Bogdan A.
AU  - Dermanovic, M
AU  - Lim, DM
AU  - Paik, YK
AU  - Tinant, B
AU  - Declerq, JP
PY  - 1997
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2600
AB  - The synthesis of Delta(7,9(11))-lanostadiene derivatives functionalized at C(32) starting from 3 beta-acetoxy-7 alpha,32-epoxylanostan-11-one has been presented. The Delta(7,9(11)) moiety was efficiently introduced in three steps in 71% yield by the regioselective abstraction of allylic 8 beta hydrogen. The formyl group of the key intermediate, 3 beta-benzoyloxylanosta-7,9(11)-dien-32-al, has been stereoselectively alkylated into (32S) derivative, whereas its oxidation unexpectedly afforded 3 beta-benxoyloxy-7-oxolanost-8-ene-32,11 alpha-lactone and not the corresponding acid. Delta(7,9(11))-lanostadienes possessing HC(32)=O, C(32)=N, HC(32S)CH3OH, H2C(32)OH, as well as some 11-keto lanostenes, were tested in vitro against several purified cholesterogenic enzymes showing moderate activity, with most the active aldehyde 16 having IC50 = 86 mu M. (C) 1997 by Elsevier Science, Inc.
PB  - Elsevier Science Inc, New York
T2  - Steroids
T1  - The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes
VL  - 62
IS  - 11
SP  - 709
EP  - 718
DO  - 10.1016/S0039-128X(97)00075-5
ER  - 

@article{
author = "Šolaja, Bogdan A. and Dermanovic, M and Lim, DM and Paik, YK and Tinant, B and Declerq, JP",
year = "1997",
abstract = "The synthesis of Delta(7,9(11))-lanostadiene derivatives functionalized at C(32) starting from 3 beta-acetoxy-7 alpha,32-epoxylanostan-11-one has been presented. The Delta(7,9(11)) moiety was efficiently introduced in three steps in 71% yield by the regioselective abstraction of allylic 8 beta hydrogen. The formyl group of the key intermediate, 3 beta-benzoyloxylanosta-7,9(11)-dien-32-al, has been stereoselectively alkylated into (32S) derivative, whereas its oxidation unexpectedly afforded 3 beta-benxoyloxy-7-oxolanost-8-ene-32,11 alpha-lactone and not the corresponding acid. Delta(7,9(11))-lanostadienes possessing HC(32)=O, C(32)=N, HC(32S)CH3OH, H2C(32)OH, as well as some 11-keto lanostenes, were tested in vitro against several purified cholesterogenic enzymes showing moderate activity, with most the active aldehyde 16 having IC50 = 86 mu M. (C) 1997 by Elsevier Science, Inc.",
publisher = "Elsevier Science Inc, New York",
journal = "Steroids",
title = "The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes",
volume = "62",
number = "11",
pages = "709-718",
doi = "10.1016/S0039-128X(97)00075-5"
}

Šolaja, B. A., Dermanovic, M., Lim, D., Paik, Y., Tinant, B.,& Declerq, J.. (1997). The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes. in Steroids
Elsevier Science Inc, New York., 62(11), 709-718.
https://doi.org/10.1016/S0039-128X(97)00075-5

Šolaja BA, Dermanovic M, Lim D, Paik Y, Tinant B, Declerq J. The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes. in Steroids. 1997;62(11):709-718.
doi:10.1016/S0039-128X(97)00075-5 .

Šolaja, Bogdan A., Dermanovic, M, Lim, DM, Paik, YK, Tinant, B, Declerq, JP, "The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes" in Steroids, 62, no. 11 (1997):709-718,
https://doi.org/10.1016/S0039-128X(97)00075-5 . .

TY  - JOUR
AU  - Todorović, Nevena M.
AU  - Stefanović, Milutin
AU  - Tinant, B
AU  - Declercq, JP
AU  - Makler, MT
AU  - Šolaja, Bogdan A.
PY  - 1996
UR  - https://cherry.chem.bg.ac.rs/handle/123456789/2582
AB  - Cholestane-derived gem-dihydroperoxides and tetraoxanes were synthesized starting from 5 alpha- and 5 beta-cholestan-3-ones by acid-catalyzed addition of hydrogen peroxide to the ketone. They were characterized by IR, NMR, and mass spectroscopy analysis aided by molecular mechanics calculations, and, in the instance of 5 beta-cholestane-3 alpha,3 beta-dihydroperoxide (6), by x-ray analysis. The synthesized compounds were tested in vitro against Plasmodium falciparum Sierra Leone (D6) and Indochina (W2) malaria clones. All compounds were inactive to both clones, with the exception of tetraoxane 7a, which exhibited modest activity toward D6 clone with IC50 = 155 nM. (C) 1996 by Elsevier Science Inc.
PB  - Elsevier Science Inc, New York
T2  - Steroids
T1  - Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity
VL  - 61
IS  - 12
SP  - 688
EP  - 696
DO  - 10.1016/S0039-128X(96)00203-6
ER  - 

@article{
author = "Todorović, Nevena M. and Stefanović, Milutin and Tinant, B and Declercq, JP and Makler, MT and Šolaja, Bogdan A.",
year = "1996",
abstract = "Cholestane-derived gem-dihydroperoxides and tetraoxanes were synthesized starting from 5 alpha- and 5 beta-cholestan-3-ones by acid-catalyzed addition of hydrogen peroxide to the ketone. They were characterized by IR, NMR, and mass spectroscopy analysis aided by molecular mechanics calculations, and, in the instance of 5 beta-cholestane-3 alpha,3 beta-dihydroperoxide (6), by x-ray analysis. The synthesized compounds were tested in vitro against Plasmodium falciparum Sierra Leone (D6) and Indochina (W2) malaria clones. All compounds were inactive to both clones, with the exception of tetraoxane 7a, which exhibited modest activity toward D6 clone with IC50 = 155 nM. (C) 1996 by Elsevier Science Inc.",
publisher = "Elsevier Science Inc, New York",
journal = "Steroids",
title = "Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity",
volume = "61",
number = "12",
pages = "688-696",
doi = "10.1016/S0039-128X(96)00203-6"
}

Todorović, N. M., Stefanović, M., Tinant, B., Declercq, J., Makler, M.,& Šolaja, B. A.. (1996). Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity. in Steroids
Elsevier Science Inc, New York., 61(12), 688-696.
https://doi.org/10.1016/S0039-128X(96)00203-6

Todorović NM, Stefanović M, Tinant B, Declercq J, Makler M, Šolaja BA. Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity. in Steroids. 1996;61(12):688-696.
doi:10.1016/S0039-128X(96)00203-6 .

Todorović, Nevena M., Stefanović, Milutin, Tinant, B, Declercq, JP, Makler, MT, Šolaja, Bogdan A., "Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity" in Steroids, 61, no. 12 (1996):688-696,
https://doi.org/10.1016/S0039-128X(96)00203-6 . .