17514-35-1Relevant academic research and scientific papers
Asymmetric synthesis of anthracyclinones: Synthesis of a new chiral AB-synthon, (5R,6R)-6-ethyl-5,6-dihydroxy-5,6,7,8-tetrahydro-1,4-naphthoquinone, and its application for a novel regioselective synthesis of (-)-γ-rhodomycinone
Fujioka,Yamamoto,Annoura,Maeda,Kita
, p. 32 - 35 (1992)
A new chiral AB-synthon, (5R,6R)-6-ethyl-5,6-dihydroxy-5,6,7,8-tetrahydro-1,4-naphthoquinone (4), for the synthesis of optically active rhodomycinones was prepared stereoselectively from a (-)-α-hydroxy ketone (6). The coupling reactions of 4 with homophthalic anhydride derivatives (9, 12) proceeded in a regioselective manner to give the tetracyclic compounds 10 and 13, respectively. Compound 10 was converted to (-)-γ-rhodomycinone (3) in a two-step sequence. The optical purity (100% ee) of 3 was unambiguously determined by high performance liquid chromatography analysis using a chiral column.
Synthetic Anthracyclinones, 37. - Total Synthesis of (+)-β-Rhodomycinone, (+)-1-Deoxy-β-rhodomycinone, and (+)-1-Deoxy-γ-rhodomycinone by Incorporation of (S)-α-Hydroxybutyric Acid
Krohn, Karsten,Hamann, Ingo
, p. 949 - 954 (2007/10/02)
Both enantiomers of the optically active building block 4 for anthracyclinone synthesis have been prepared from α-hydroxybutyric acid 7.Key steps were the diastereoselective alkylation of the acetal 5 to 8 followed by DIBAH reduction and transacetalization to 10.Coupling of 4 to quinizarine (11) and 1,4,5-trihydroxy-9,10-anthraquinone (3) by two successive Marschalk reactions and benzylic hydroxylation afforded the natural product (+)-β-rhodomycinone (18) and (+)-1-deoxy-β-rhodomycinone (17).
SYNTHETIC ANTHRACYCLINONES-XXVII. ANTHRACYCLINONES BY INTRAMOLECULAR MARSCHALK REACTION. SYNTHESIS OF THE FEUDOMYCINONES AND RHODOMYCINONES.
Krohn, Karsten,Priyono, Wahyudi
, p. 4609 - 4616 (2007/10/02)
1,4,5-Trihydroxy-9,10-anthraquinone is transformed regioselectively to the α-hydroxy dichlorides 18-21, which are cyclized to yield predominantely the naturally configurated 9,10-trans-diols 1,3,26, and 27 (80 to 96percent d.e.).The monotrifluoroacetates 38-40 derived from the trans-diols are hydroxylated via bromination at C-7 to yield almost exclusively the 7,9-cis-9,10-trans-triols α1-rhodomycinone (4), feudomycinone D (7), and 4-O-methyl-β-rhodomycinone (42).The feudomycinones A (5) and C (6) are obtained with less chemo- and stereoselectivity by hydroxylation of the 10-deoxycompounds 33 and 34.
A REGIOSELECTIVE SYNTHESIS OF DAUNOMYCINONE AND RELATED ANTHRACYCLINONES.
Braun, Manfred
, p. 4585 - 4592 (2007/10/02)
The phthalic anhydrides 4a and 4b are attacked by the Grignard reagents 15 and 33 in tetrahydrofuran/tetramethylethylene diamine almost exclusively at the carbonyl group, which is situated in the meta position of the methoxy substituent(s).This highly reg
Synthetic Anthracyclinones, XXII. - Rhodomycinones of Type A with Methyl, Ethyl, and n-Propyl Side Chain
Krohn, Karsten,Behnke, Bert
, p. 1818 - 1838 (2007/10/02)
The anthraquinone derivatives 7, 8, 37, 39, and 40 are prepared by addition of dichloromethyllithium to the corresponding ketones 4, 5, 32b, 34b, and 36b.They can be hydrolized to intermediate aldehydes, which cyclize after reduction to anthracyclinones of Type A with methyl group (11, 12a, 13a, 45, 46a, 47a), ethyl group (15a, 16a, 48, 49, 50a), and n-propyl side chain (51a, 52a).The cis/trans ratio of the 7,8-Diols is approximately 1 : 3.The hydroxy groups at C-10 are introduced stereoselectively to the 8,10-cis-diols 20b, 24, 25a, 53, 54, and 55 via bromination and hydrolysis of the bromides.
REGIOSELECTIVE SYNTHESE VON DAUNOMYCINON UND γ-RHODOMYCINON
Braun, Manfred
, p. 3871 - 3874 (2007/10/02)
Synthesis of daunomycinone (2) and γ-rhodomycinone (3) by regioselective addition of the Grignard reagents 9b and 9d to the anhydride 4.
