Five new compounds, including a benzopyran ribonic glycoside, daldiniside A (1), two isocoumarin ribonic glycosides, daldinisides B (2) and C (3), and two alkaloids, 1-(3-indolyl)-2R,3-dihydroxypropan-1-one (4) and 3-ethyl-2, 5-pyrazinedipropanoic acid (5), along with five known compounds (6-10), were isolated from the EtOAc extract of the marine-associated fungus, Daldinia eschscholzii. Their structures were elucidated by extensive physicochemical and spectroscopic properties, besides comparison with literature data. The absolute configurations of compounds 1-3 were corroborated by chemical transformation, GC analysis and X-ray crystallographic analysis. Meanwhile, the absolute configuration of compound 4 and the planar structure of compound 6 were also determined based on the X-ray diffraction analysis. The cytotoxicity of compounds 1-10, antifungal and anti-HIV activities of compounds 1-5 and the in vitro assay for glucose consumption of compounds 1-3 were done in the anti-diabetic model, whereas none showed obvious activity.

hydrolysis, secondary metabolites, marine-associated fungus, Daldinia eschscholzii, GC analysis, X-ray diffraction analysis

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10
5	aDRibf	103.4	73.9	71.4	88.5	63.5
	Subst	68.8	38.9	60.1	116.1	158.6	107.9	130.5	112.0	157.4	21.6


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6	H7	H8	H9	H10
5	aDRibf	5.70	4.23	4.10	4.20	3.64-3.69
	Subst	4.21	1.68-2.01	5.04	-	-	6.72	7.12	6.49	-	1.40


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6	C7/H7	C8/H8	C9/H9	C10/H10
5	aDRibf	103.4/5.70	73.9/4.23	71.4/4.10	88.5/4.20	63.5/3.64-3.69
	Subst	68.8/4.21	38.9/1.68-2.01	60.1/5.04			107.9/6.72	130.5/7.12	112.0/6.49		21.6/1.40

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

C[C@@H]1C[C@@H](O)c2c(cccc2O[C@H]2O[C@H](CO)[C@@H](O)[C@H]2O)O1

312.318 g/mol (C₁₅H₂₀O₇)

Five new compounds, including a benzopyran ribonic glycoside, daldiniside A (1), two isocoumarin ribonic glycosides, daldinisides B (2) and C (3), and two alkaloids, 1-(3-indolyl)-2R,3-dihydroxypropan-1-one (4) and 3-ethyl-2, 5-pyrazinedipropanoic acid (5), along with five known compounds (6-10), were isolated from the EtOAc extract of the marine-associated fungus, Daldinia eschscholzii. Their structures were elucidated by extensive physicochemical and spectroscopic properties, besides comparison with literature data. The absolute configurations of compounds 1-3 were corroborated by chemical transformation, GC analysis and X-ray crystallographic analysis. Meanwhile, the absolute configuration of compound 4 and the planar structure of compound 6 were also determined based on the X-ray diffraction analysis. The cytotoxicity of compounds 1-10, antifungal and anti-HIV activities of compounds 1-5 and the in vitro assay for glucose consumption of compounds 1-3 were done in the anti-diabetic model, whereas none showed obvious activity.

hydrolysis, secondary metabolites, marine-associated fungus, Daldinia eschscholzii, GC analysis, X-ray diffraction analysis

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10	C11
6	aDRibf	101.8	73.6	71.2	88.3	63.3
	Subst	167.8	-	155.9	105.8	141.2	104.5	166.1	103.9	164.5	101.4	19.4


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6	H7	H8	H9	H10	H11
6	aDRibf	5.74	4.24	4.12	4.15	3.65-3.72
	Subst	-	-	-	6.31	-	6.58	-	6.62	-	-	2.22


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6	C7/H7	C8/H8	C9/H9	C10/H10	C11/H11
6	aDRibf	101.8/5.74	73.6/4.24	71.2/4.12	88.3/4.15	63.3/3.65-3.72
	Subst				105.8/6.31		104.5/6.58		103.9/6.62			19.4/2.22

The spectrum also has 1 signal at unknown position (not plotted).

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

Cc1cc2cc(O[C@H]3O[C@H](CO)[C@@H](O)[C@H]3O)cc(O)c2c(=O)o1

324.285 g/mol (C₁₅H₁₆O₈)

Five new compounds, including a benzopyran ribonic glycoside, daldiniside A (1), two isocoumarin ribonic glycosides, daldinisides B (2) and C (3), and two alkaloids, 1-(3-indolyl)-2R,3-dihydroxypropan-1-one (4) and 3-ethyl-2, 5-pyrazinedipropanoic acid (5), along with five known compounds (6-10), were isolated from the EtOAc extract of the marine-associated fungus, Daldinia eschscholzii. Their structures were elucidated by extensive physicochemical and spectroscopic properties, besides comparison with literature data. The absolute configurations of compounds 1-3 were corroborated by chemical transformation, GC analysis and X-ray crystallographic analysis. Meanwhile, the absolute configuration of compound 4 and the planar structure of compound 6 were also determined based on the X-ray diffraction analysis. The cytotoxicity of compounds 1-10, antifungal and anti-HIV activities of compounds 1-5 and the in vitro assay for glucose consumption of compounds 1-3 were done in the anti-diabetic model, whereas none showed obvious activity.

hydrolysis, secondary metabolites, marine-associated fungus, Daldinia eschscholzii, GC analysis, X-ray diffraction analysis

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10	C11	C12	C13
6	aDRibf	102.1	74.1	71.3	89.0	63.4
	Subst	167.0	-	156.7	106.7	140.5	104.3	165.9	103.7	164.1	101.5	44.3	65.4	24.4


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6	H7	H8	H9	H10	H11	H12	H13
6	aDRibf	6.17	4.87	4.85	4.88	4.12-4.17
	Subst	-	-	-	6.40	-	6.70	-	6.89	-	-	2.67-2.74	4.45	1.40


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6	C7/H7	C8/H8	C9/H9	C10/H10	C11/H11	C12/H12	C13/H13
6	aDRibf	102.1/6.17	74.1/4.87	71.3/4.85	89.0/4.88	63.4/4.12-4.17
	Subst				106.7/6.40		104.3/6.70		103.7/6.89			44.3/2.67-2.74	65.4/4.45	24.4/1.40

The spectrum also has 1 signal at unknown position (not plotted).

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

C[C@H](O)Cc1cc2cc(O[C@H]3O[C@H](CO)[C@@H](O)[C@H]3O)cc(O)c2c(=O)o1

368.338 g/mol (C₁₇H₂₀O₉)