Anti-babesial ellagic acid rhamnosides from the bark of Elaeocarpus parvifolius.

Bioassay-guided investigation of the bark of Elaeocarpus parvifolius led to the isolation of three new ellagic acid derivatives, 4-O-methylellagic acid 3'-alpha-rhamnoside (2), 4-O-methylellagic acid 3'-(3''-O-acetyl)-alpha-rhamnoside (3), and 4-O-methylellagic acid 3'-(4''-O-acetyl)-alpha-rhamnoside (4) in addition to the known ellagic acid derivative, 4-O-methylellagic acid 3'-(2'',3''-di-O-acetyl)-alpha-rhamnoside (1). Their structures were elucidated on the basis of analysis of 1H NMR, 13C NMR, HMQC, HMBC and MS spectroscopic data. Compounds 1-4 were evaluated for their growth-inhibitory effect on Babesia gibsoni in vitro. Compounds 2 and 4 showed very weak activity, while compounds 1 and 3 showed moderate activity, with IC50 values of 28.5 and 52.1 microg/ml, respectively.

Labeling patterns of chloroplastidic isoprenoids in cultured cells of liverwort Ptychanthus striatus.

Incorporation studies administering 2H- and 13C-labeled mevalonate (MVA) and 13C-labeled glucose to suspension cultured cells of the liverwort, Ptychanthus striatus, were carried out in order to examine the biosynthesis of the phytyl side-chain of chlorophyll a. Administration of 13C- and 2H-labeled MVA provided evidence for the involvement of the MVA pathway in the phytyl side-chain biosynthesis and preferential labeling of the farnesyl diphosphate (FPP)-derived portion. An alternate labeling pattern in the phytyl side-chain was observed which was slightly different to the non-equivalent labeling in other liverworts, such as Heteroscyphus planus and Lophocolea heterophylla and in the hornwort, Anthoceros punctatus. The labeling pattern observed after the administration of 13C-labeled glucose revealed the simultaneous involvement of the non-MVA pathway in the phytol biosynthesis of P. striatus cells.

Stable isotope-labeling studies on the oxidative coupling of caffeic acid via o-quinone.

The formation of ortho-quinone from ortho-diphenol is a key step in its dimerization. An NMR analysis of the oxidation of 3,4-dihydroxycinnamic acid (caffeic acid) by NaIO4 revealed the formation of 3-(3',4'-dioxo-1',5'-cyclohexadienyl) propenoic acid (o-quinone) prior to the formation of furofuran-type lignan 4,8-exo-bis (3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3.3.0]octane-2,6-dione. Both electrolytic and enzymatic oxidation of caffeic acid also generated o-quinone. The yields of o-quinone from caffeic acid were quantified by NMR and HPLC analyses. A stable isotope-labeling study of the formation of lignans directly proved the random radical coupling of semiquinone radicals formed from a set of caffeic acid and o-quinone.

Novel photoreactive cinnamic acid analogues to elucidate phenylalanine ammonia-lyase.

4-[3-(Trifluoromethyl) diazirinyl] cinnamic acid derivatives were synthesized to elucidate properties of phenylalanine ammonia-lyase (PAL). 2-Methoxy and 2-biotinylated alkoxy compounds have inhibitory activity on the formation of phenylalanine from cinnamic acid. Specific photolabeling of the enzyme was detected using biotinylated derivatives without the use of radioisotopes. The results indicated that the 4-[3-(trifluoromethyl) diazirinyl] skeleton will be a suitable photoreactive compound to elucidate regulation of phenylpropanoid biosynthesis.

Nonequivalent labeling of the phytyl side chain of chlorophyll a in callus of the hornwort Anthoceros punctatus.

Callus cultures of the hornwort Anthoceros punctatus were induced from the apical portions of the gametophytes. Calli can accumulate rosmarinic acid, which is suggested as an intermediate for anthocerotonic acid, a rare phenylpropanoid dimer with a cyclobutane ring, indicating that calli possess the ability to produce secondary metabolites found primarily in intact plants. Biosynthesis of chloroplastidic terpenoids of liverworts showed preferential labeling of the farnesyl diphosphate (FPP)-derived portion in the phytyl side chain of chlorophyll a (1) when calli of A. punctatus are incubated with (2)H- and (13)C-labeled mevalonate. This finding suggests either that cytoplasmic FPP (or isopentenyl diphosphate, IPP) is taken into chloroplasts and condensed with endogenous IPP derived from a nonmevalonate pathway, or that FPP is synthesized within chloroplasts from extraplastidically formed IPP (or mevalonate) and then condensed with endogenous IPP in a different subplastidic fraction.

Biosynthesis of depudecin, a metabolite of Nimbya scirpicola.

Feeding experiments of labeled acetates to Nimbya scirpicola proved the carbon origin of the straight-chain polyketide, depudecin. Differential hydrogen exchange of the 2H label originating from 2H labeled acetate along the polyketide chain occurred. In particular, the deuterium of an epoxide methine at C-3 was lost to a substantial extent in the formation of depudecin.

1,2-Hydride Shift in the Biosynthesis of Pinguisane-type Sesquiterpenes.

A (2)H-NMR analysis of 6α-hydroxy-3-oxo-pinguis-5(10)-ene-11,6-olide produced by axenic culture of liverwort Aneura pinguis in the presence of [4-(2)H2]-labeled mevalonate clarified the presence of a 1,2-hydride shift and retention of deuterium at the C-4 position in the biosynthesis of pinguisane-type sesquiterpenes from FPP.

Absolute Configuration of Kelsoene and Prespatane.

The absolute configurations of the rare sesquiterpenes, kelsoene and prespatane, were determined to be (1S, 2R,5S, 6S, 7R, 8R)-2,8-dimethyl-6-(1-methylethenyl)tricyclo[5.3.0.0(2,5)] decane (IUPAC name) and (1R, 2S, 5R, 6R, 7R, 8S)-1,5-dimethyl-8-(1-methylethenyl) tricyclo-[5.3.0.0(2,6)] decane, respectively, on the basis of the observed chemical shifts and NOEs in NOESY and NOEDS experiments after conversion with the chiral reagent, 2'-methoxy-1,1'-binaphthalene-2-carbohydroximoyl chloride (MBCC). The absolute configurations of kelsoene and prespatane thus determined suggest that initial cyclization of FPP from the si-face at C-10 to form a 10R-germacradienyl cation leads to kelsoene, while that from the re-face leads to prespatane via the 10S-germacradienyl cation.

Erimopyrone, a Lignan Derivative from the Liverwort Moerckia erimona.

The new lignan derivative, erimopyrone, was isolated from the liverwort, Moerckia erimona. Its structure was established as [1R, 2S]-1(6-carboxy-2-oxo-2H-4-pyranyl)- 6,7-dihydroxy-1,2-dihydro-2,3-naphthalenedicarboxylic acid by spectroscopic methods.

Biosynthesis of striatol in cultured cells of liverwort, Ptycanthus striatus.

NMR analyses of striatol produced by suspension-cultured cells of liverwort, Ptycanthus striatus, in the presence of [2-(13)C]- and [4,4-(2)H2]-MVAs confirmed proton-catalyzed cyclization between the distal and central double bonds in FPP and a concerted series of 1,2-migrations of hydrogen and a methyl group, with subsequent elimination of a proton.

Fiberoptic ductoscopy of the breast: a new diagnostic procedure for nipple discharge.

A fiberoptic ductoscopy system was successfully developed by means of which we were able to observe the duct cavity of the breast. Two kinds of silicafiberscopes with outer diameters 0.80 and 0.45 mm were used in the present study. Fiberoptic ductoscopy was applied to 52 ducts in 46 patients with nipple discharge for whom no tumor was palpable; the intraductal appearance could be observed in 47 ducts from 41 patients (90.3%). Fourteen ducts from 13 patients were operated upon and were histologically diagnosed as carcinoma (four cases), intraductal papilloma (nine ducts from eight patients) and mastitis (one case). The internal surface of a normal duct was lustrous and smooth. Cancer growing on the surface of a duct wall appeared white and was slightly elevated, forming a bridging structure. The intraductal papillomas formed intraductal solid nodules, being yellow in most cases and red at the site of hemorrhage. Fiberoptic ductoscopy can be used to recognize the growth of minute intraductal lesions in cases of nipple discharge. Clinical endoscopic diagnosis for minute intraductal lesions will make an important contribution to the early detection of cancer and the evaluation of nipple involvement in intraductal carcinoma.

Histological characteristics and postoperative course of gastric carcinoma.

The histological features of gastric carcinoma in patients survived more than 5 years after the resection were reviewed. In general prognosis and length of survival were related clearly to the degree of malignancy of cancer. Duration of the remission was also reciprocaly related. Certain type of carcinoma simplex or undifferentiated carcinoma was associated with unexpectedly more favorable prognosis. Paradoxical relation was also demonstrated between degree of atypism in adenocarcinoma papillare with introversive pseudopapillary pattern and its prognosis.