(S)-4-Methoxydalbergione

Contact dermatitis of the lips due to late-type sensitization against dalbergiones in a wooden recorder.[Pubmed:31826027]

Allergol Select. 2018 Sep 1;2(1):29-31.

BACKGROUND: Late-type sensitizations against wood are rare and are mostly seen in patients with occupational contact with saw dust. Generally, commercial wooden products only lead to sensitization or dermatitis in cases when contact to the unprotected skin is direct, intensive and of longer duration, i.e. by wearing wooden jewelry or by playing wooden instruments. Causative for the sensitization process are ingredients of the wood core such as alkaloids, glycosides, anthrachinones, saponines, phenols, catechols, flavonoids, cumarins, and benzo-, naphtho-, furano-, and phenanthrenquinones and their precursors. CASE REPORT: We report the case of a 70-year-old patient who developed cheilitis after playing different wooden recorders made of African blackwood, rosewood, cedar, olive, and pear. METHODS: Patch testing with baseline series of contact allergens and saw dust of the recorders were performed as well as skin prick tests with common inhalant allergens and saw dust of the recorders. RESULTS: Patch testing showed sensitizations against African blackwood, rosewood, fragrance mix 2 and hydroxyisohexyl-3-cyclohexene carboxaldehyde. Skin prick testing was without pathological results. CONCLUSION: African blackwood and rosewood contain (S)-4'-hydroxy-4-methoxydalbergione and (S)-4-Methoxydalbergione. As a result of the chemical affinity between the dalbergiones, cross-reactions between different woods are observed. The case presented shall show the diagnostic procedure in cases in which sensitizations against wood components are suspected.

Catalytic asymmetric addition of Meldrum's acid, malononitrile, and 1,3-dicarbonyls to ortho-quinone methides generated in situ under basic conditions.[Pubmed:25766504]

Chemistry. 2015 Apr 13;21(16):6037-41.

A new approach to the utilization of highly reactive and unstable ortho-quinone methides (o-QMs) in catalytic asymmetric settings is presented. The enantioselective reactions are catalysed by bifunctional organocatalysts, and the o-QM intermediates are formed in situ from 2-sulfonylalkyl phenols through base-promoted elimination of sulfinic acid. The use of mild Bronsted basic conditions for transiently generating o-QMs in catalytic asymmetric processes is unprecedented, and allows engaging productively in the reactions nucleophiles such as Meldrum's acid, malononitrile and 1,3-dicarbonyls. The catalytic transformations give new and general entries to 3,4-dihydrocoumarins, 4H-chromenes and xanthenones. These frameworks are recurring structures in natural product and medicinal chemistry, as testified by the formal syntheses of (R)-tolterodine and (S)-4-Methoxydalbergione from the catalytic adducts.

Enantioselective addition of boronates to o-quinone methides catalyzed by chiral biphenols.[Pubmed:23206197]

J Am Chem Soc. 2012 Dec 12;134(49):19965-8.

Chiral biphenols were found to catalyze the enantioselective asymmetric addition of aryl- or alkenylboronates to o-quinone methides. Substituted 2-styryl phenols were obtained in good yields (up to 95%) with high enantiomeric ratios (up to 98:2) in the presence of 10 mol % 3,3'-Br(2)-BINOL. A two-step synthesis of (S)-4-Methoxydalbergione in good yield and selectivity was achieved.

Three new flavonoids and antiallergic, anti-inflammatory constituents from the heartwood of Dalbergia odorifera.[Pubmed:9525107]

Planta Med. 1998 Mar;64(2):153-8.

Three new flavonoids, (3R)-4'-methoxy-2',3,7-trihydroxyisoflavanone (11), 7-methoxy-3,3',4',6-tetrahydroxyflavone (18), and 2',7-dihydroxy-4',5'-dimethoxyisoflavone (22), were isolated from the heartwood of Dalbergia odorifera T. Chen. (Leguminosae), together with twenty-two known compounds, (S)-4-Methoxydalbergione (1), cearoin (2), medicarpin (3), formononetin (4), sativanone (5), 3-hydroxy-9-methoxy-coumestan (6), meliotocarpan A (7), isoliquiritigenin (8), stevein (9), liquiritigenin (10), 3',4',7-trihydroxyflavanone (12), butein (13), 3'-hydroxymelanettin (14), koparin (15), bowdichione (16), fisetin (17), melanettin (19), sulfuretin (20), 3'-hydroxydaidzein (21), 3'-O-methylviolanone (23), xenognosin B (24), and dalbergin (25). These flavonoids were evaluated in antiallergic and anti-inflammatory tests. The results showed that (S)-4-Methoxydalbergione (1) and cearoin (2) exhibited antiallergic activity while (S)-4-Methoxydalbergione (1), cearoin (2), butein (13), koparin (15), bowdichione (16), 3'-O-methylviolanone (23), and xenognosin B (24) showed significant anti-inflammatory activity.