The new depsides decarboxyhypothamnolic acid
[3-(2′,4′-dihydroxy-3′,6′-dimethylphenyloxycarbonyl)-2-
hydroxy-6-methoxy-4-methylbenzoic acid] (4) and cryptothamnolic acid
[3-(3′-formyl-2′-hydroxy-4′-methoxy-
6′-methylbenzoyloxy)-4,6-dihydroxy-2,5-dimethylbenzoic acid] (6)
have been detected in extracts of a Chinese Pertusaria
species together with hypothamnolic acid (3) and their structures implied by
means of chromatographic and spectroscopic comparisons with synthetic
materials. Two further new depsides, neothamnolic acid
[3-(5′,7′- dihydroxy-6′ -methyl-1′ -oxo-1′
,3′ -dihydroisobenzofuran-4′
-yloxycarbonyl)-2-hydroxy-6-methoxy-4- methylbenzoic acid] (8) and
lactothamnolic acid
[3-(6′-formyl-5′,7′-dihydroxy-1′-oxo-1′,3′-dihydroisobenzo-
furan-4′-yloxycarbonyl)-2-hydroxy-6-methoxy-4-methylbenzoic acid]
(9), have been isolated from the lichen
Siphula ramalinoides, and the structure of these
compounds followed from a combination of spectroscopic data, derivatization
and degradation experiments.
癸羧基百帕萘酸的新去苷类化合物
[3-(2′,4′-二羟基-3′,6′-二甲基苯基氧羰基)-2-羟基-6-甲氧基-4-甲基苯甲酸] (4)
羟基-6-甲氧基-4-甲基苯甲酸] (4)和隐莰烷酸
[3-(3′-formyl-2′-hydroxy-4′-methoxy-
6′-甲基苯甲酰氧基)-4,6-二羟基-2,5-二甲基苯甲酸] (6)
的提取物中检测到。
酸(3),并通过色谱和光谱分析暗示了它们的结构。
色谱法和光谱法与合成材料进行比较,从而推断出它们的结构。
的结构。另外两种新的苷类,即新槐酚酸
[3-(5′,7′-二羟基-6′-甲基-1′-氧代-1′)
3′-二氢异苯并呋喃-4′-酰氧基羰基
-2-羟基-6-甲氧基-4-甲基苯甲酸] (8) 和
乳香酚酸
[3-(6′-formyl-5′,7′-dihydroxy-1′-oxo-1′,3′-dihydroisobenzo-
呋喃-4′-基氧羰基)-2-羟基-6-甲氧基-4-甲基苯甲酸](9)中分离出来。
(9),已从地衣中分离出来
从地衣 Siphula ramalinoides 中分离出了这些化合物。
这些化合物的结构是根据光谱数据、衍生和降解实验得出的。
和降解实验。