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Three isomers of 2H,8H-benzo[1,2-b: 3,4-b′]dipyran and 2H,8H-benzo[1,2-b: 5,4-b′]dipyran, were synthesized by dehydrogenation of the dihydrobenzodipyran derivatives using DDQ or NBS and by dehydration of the secondary alcohol prepared by reduction of 4-phenylcoumarin derivatives bearing dihydropyranone ring with sodium borohydride.

(±)-Vitrenal (1), a sesquiterpene aldehyde with a novel vitrane skeleton, was synthesized from a monoterpene piperitenone (2) by 12-step reactions in ca. 7% overall yield. 2-Formyl-isocarane, derived from 2 via (±)-isocaran-2-one was allylated stereospecifically and, after protection of the formyl group, the allyl chain was modified to a 4-methoxy-3-butenyl group. Acid treatment of the masked dialdehydic intermediate yielded 1 by concomitant deprotection and aldol condensation.

The structure and absolute configuration of a new cyclopentenone derivative, (+)-kjellmanianone, isolated from the brown alga Sargassum kjellmanianum has been determined as 5-carbomethoxy-5-hydroxy-3-methoxy-2-cyclopenten-1-one on the basis of the chemical and spectroscopic evidence and the X-ray analysis.

The mass spectrum of desmethylencecalin has been measured and a fragmentation mechanism for the loss of a water molecule from the [MCH3]+ ion is proposed on the basis of isotope labelling and metastable peak observations. The eliminated water has been shown to involve the carbonyl oxygen and hydrogen atoms of the hydroxyl and acetyl groups.

The structures and conformations of 6β,12β-dihydroxy-3E,7E-dolabelladiene 6-p-bromobenzoate and acetoxyodontoschismenol 3S,4S-epoxide have been established By X-ray crystallographic analysis. The original assignment of the stereochemistry at C-12 of (+)-acetoxyodontoschismenol has been revised.

Ion kinetic energy spectroscopy(IKES)provides new and useful information on the structure of ions formed by mass spectrometer. This method was applied to the distinc tion of isomeric monoterpene pairs whose mass spectra are nearly identical. It is shown that the IKE spectra can be used for such isomers, which was exemplified by the case of borneol and iso-borneol.

A series of the enantiomeric sesquiterpenoids corresponding to the antipodos of those obtained from higher plants were isolated from the liverwort Riccardia jackii. This result is an additional example suggesting the special position taxonoinical of the liverworts in plant kingdom

The mass spectra of fifteen diterpenoids belonging to the new carbon skeletons of verrucosane, neoverrucosane and homoverrucosane are examined. From their spectra the relationship between fragmentation patterns and substituted modes of these diterpenoids is discussed.

Ammonia and isobutane chemical ionization mass spectra of the intact flavone glycosides are described. The protonated molecular ion(MH+) are peaks very weak and glycosidic bond cleavage is observed as the major fragmentation pathway. Consequently, the mass spectra exihibit the protonated aglycone ions as the base peak and the various sugar-derived ions.

Mass spectra of three naturally occurrig ent-15-ketokauranoids, (I), (III)and(IV), and their derivatives, (II)and(V), were measured and their characteristic fragmentations were discussed.

Three new monoacetates of diterpene diols were isolated from Mylia verrucosa and the structures were determined as [2], [3] and [9] on the basis of chemical and spectral evidence.

The doubly charged ion mass spectra of anhydropisatin, 4-methoxyanhydropisatin, 3, 8, 9-trimethoxypterocarpen and 3, 4, 8, 9-tetramethoxypterocarpen were determined, and the fragmentation was explained by assuming that the paired electrons were partially localized in the fragmentations and by comparing the spectra with that of 3-(CD3)-anhydropisatin. Conventional mass spectra of these compounds were very simple, but the doubly charged ion spectra were sufficiently characteristic for the reliable identification.

The structure of dihydroxyverrucosane (I), a novel diterpene-diol isolated from the liverwort Mylia verrucosa has been determined from single-crystal X-ray analysis of the mono-p-bromobenzoate (II) by the heavy-atom method. The crystals were monoclinic, a= 6.670(1), b= 19.269(1), c= 10.379(1)A, β= 112.6(4)°, space group P21, Z= 2. Block-diagonal least-squares refinement based on 1 929 independent reflections converged to R 0.078. The absolute configuration was established by the anomalous dispersion effect. The molecule contains a 3,6,6,5-tetracyclic ring system in which ring B is considerably distorted by fusion with the cyclopropane ring A. Ring C adopts a chair conformation and ring D is a conformation somewhere between a half-chair and β-envelope.

The mono p-bromobenzoate of the diol derived from α-pompene has been studied by X-ray crystal structure analysis and determined to be 9-p-bromobenzoxy-8-hydroxy-1,2,6,8-tetramethyltricyclo[5.3.1.02,6]undecane. The crystals are of the orthorhombic space group P212121, a=46.53(2), b=12.20(2), c=7.39(2) A, Z=8, and hence there are two independent molecules per asymmetric unit. The structure was solved by the heavy-atom methods, and refined by block-diagonal least-squares calculations to a final R value of 0.103 for 2493 observed reflections. The structures of the two independent molecules in the asymmetric unit are quite similar. Both molecules contain a tricyclo[5.3.1.02,6]undecane ring in which three fused rings (cyclohexane, cyclopentane, and cyclopentane) are present. The overall configuration of these three fused rings can be described as a “cis” type. The conformation of the cyclohexane ring is of a chair form, and the two cyclopentane rings exhibit envelope forms. Based on the anomalous X-ray dispersi...

Three sesquiterpene phenols with an ent-herbertane skeleton have been isolated from the liverwort Herberta adunca, and the elucidation of their structures and absolute configurations has been achieved on the basis of the chemical and spectral evidence.

Three labdane type diterpene glycosides ( 1 , 2 and 3 ) with 6-deoxy-L-idose have been isolated from Aster spathulifolius Maxim. and their structures have been determined on the basis of chemical and spectral data.

A sesquiterpene aldehyde, (−)-lepidozenal, having a novel trans-fused bicyclo[8.1.0]undecane carbon skeleton has been isolated from the liverwort Lepidozia vitvea, and its structure and absolute configuration have been shown to be (6S,7R)-lepidoza-1(10)E,4E-dien-14-al, on the basis of the chemical and spectral evidence.

Two enantiomeric cuparene-type sesquiterpenoids, (R)-(−)-cuparene ( 1 ) and (R)-(−)-δ-cuparenol ( 2 ), have been isolated from the liverwort, Bazzania pompeana . The structures and absolute configurations of the two compounds have been determined.

13C NMR spectra of several 2,3-seco-alloaromadendrane-type acetyl hemiacetals were analysed and the structure of an additional plant growth-inhibitor was determined to be (+)-9α-acetoxyovalifoliene. The biological activity of the new compound is also described.

Unsaturated acyclic alcohols of carbon numbers four and five reacted with boron trifluoride etherate to give eight ethers. Of these ethers, novel acyclic di- and tri-ethers were found in the reaction products of 2-methyl-2-propen-1-ol. Boron trifluoride etherate catalyzes double-bond migration, allylic rearrangement, intermolecular dehydration, and Markownikov addition reactions in unsaturated aliphatic alcohols.

The structure and absolute configuration of (–)-taylorione, isolated from the liverwort, Mylia taylorii, was elucidated to be ent-1,10-seco-aromadendra-1(5),4(15)-dien-10-one (1) on the basis of chemical and spectral evidence.

Three new sesquiterpenoids were isolated from the liverwort Marsupella emarginata subsp. tubulosa. The structures and absolute configurations of the compounds have been shown to be (−)-marsupellone(1), (+)-marsupellol(2) and (+)-acetoxymarsupellone(3), containing an ent-longipinane skeleton, on the basis of chemical and spectral evidence.

dl-Borneol and dl-isoborneol, when separately submitted to the action of boron trifluoride etherate at room temperature, gave different ethers; the one from borneol was characterized as bornyl isobornyl ether, and the other from isoborneol, as diisobornyl ether. The ethers were also obtained from borneol and isoborneol in the reaction with zinc chloride. When d-borneol was used, an optically-active bornyl isobornyl ether was obtained.

Mass spectra of some o-hydroxyacetophenones were studied. The fragmentation is discussed on the basis of high resolution data and deuterium labeling. The resulting fragment patterns are clearly influenced by the position of the methoxy group.It is shown that the significant structural information can be obtained from mass spectra of o-hydroxyacetophenones.

The mass spectra of 4-methoxy (6), 3, 4-dimethoxy (halkendin) (1), 4-ethoxy-3-methoxy (12) furo(3, 2: 6, 7)coumarin, and their 2, 3 dihydrocompounds (7, 8, 13) are recorded in Figs.1, 3, 4, 6 and 7. The fragmentation is discussed on the basis of high resolution data, metastable ion evidences, and deuterium labelling studies (Tables ltv8 and Figs.2, 5, 9 and 10).The spectrum of halkendin (Z) shows a major breakdown pathway involving initial loss of a methyl radical from Cs methoxy group followed by expulsion of CQ, then successive loss of CO, CH3(C4), and CO(Fig.5).4-Ethoxycoumarin 12 shows Ioss of ethylene om C, side chain giving an ion m/e 232 whose further fragmentation is very similar to that of 4-hydroxycoumarin derivatives (Fig.10). op.It is shown that significant structural information can be obtained from the mass spectra of 3, 4-dialkoxyfurocoumarins.

From the first crop of P. graveolens and the first and third ones of P. roseum Bourbon, low-boiling compounds escaping during the steam distillation were collected, and examined through gas chromatography and the preparation of their derivatives. Nine hydrocarbons, five carbonyl compounds, three alcohols, two esters and one sulfide were identified. Among these twenty compounds, sixteen compounds except dimethyl sulfide, α-pinene, myrcene and limonene were newly identified in the geranium species. Appreciable variation between the species was observed in contents of methanol, acetone, dimethyl sulfide and terpene hydrocarbons.

The catalytic action of several solid supports, that is, glass, rock crystal, quartzite, sea sand, unglazed porcelain and commercial supports, have been examined. Glass shows practically no catalytic action in the examined terpene compounds, except for linalyl acetate and α-santalol, which were decomposed and/or isomerized slightly, but this support does show an adsorption of oxygen-containing compounds. The catalytic action of rock crystal is slightly greater than that of glass, but the adsorptivity of rock crystal is extremely small. Commercial diatomaceous earth supports show a remarkable catalytic action.

The liquid chromqtographic behavior of mono, terpenoids qn porous polymer (Hitachi gel #3010) was investigated in methanol or n-hexane. Both varibus kinds of column sizes and flow rates of the solvent were examined, and the excellent mutual separation of monoterpenoids was obtained by using column 50 cm x g mm and flow rate 60 ml/hr in methanol.Based upon the above eondition, alcehols, carbonyl compounds and hydrocarbonds of monoter penoids could be separated satisfactory, in each case.

Mass spectra of pterocarpan derivatives (I∼VII) are recorded in Figs. 1∼5 and Tables 1∼6. The major fragmentation pathways of these compounds are shown in Scheme1. The results illustrate that the observed fragmentation patterns are of considerable utility in the application of mass spectro metry to structure elucidation in this series.

Ion kinetic energy(IKE)spectrum of β-phenylethyl cinnamate is presented(Fig. 2). The molecularion of β-phenylethyl cinnamate undergoes several decompositions, three of which are the loss of H2O, COOH and HCOOH. To study these processes, the high resolution mass spectrometry and IKE spectrum of. β-phenylethyl cinnamate were studied. Some of the fragmentation pathways of β-phenylethyl cinnamate are shown in Fig. 6.

水晶,ケイ石,ケイ砂,素焼磁器,ガラス,数種の市販担体などのモノテルペン化合物およびセスキテルペンアルコール類に対する接触作用を,これらの化合物のガスクロマトグラフィーを行なう条件に近い温度で検討した。ガラス粉末では酢酸リナリルとα-サンタロールにわずかに分解が認められる程度で,その他のテルペン化合物には分解が認められなかった。水晶,ケイ石およびケイ砂の接触作用は大体同程度であったが,これらの接触作用はガラス粉末のそれよりもいくぶん大きく,酢酸リナリルと5種のセスキテルペンアルコール類にかなりの分解が認められた。素焼磁器粉末および市販担体の接触作用は非常にはげしく,テルペン化合物の分析用担体としては改良ケイソウ土レンガ担体でもなお満足なものとはいえない。

22種のテルペン炭化水素類のクロマトグラ本を,4種の固定相(PEG6000,TCP,squalene,squalane)について検討した。試料注入量と保持時間の関係を各炭化水素について決定し,試料量ぜロにおける各試料の内部標準物質(1,8-シネオール, シクロヘキサノール) に対する絶対的相対保持値を決定した。また調合試料につき各固定相を用いた場合の分離能について検討した。その結果,いずれの固定相を用いた場合も各炭化水素の溶出順位は大体沸点順位と一致した。また試料注入量の増加により保持時間が大となり,溶出順位のおそいものほどこの傾向が顕著であった。PEG6000では尖鋭なピークが得られ分離能が最もよく, 試料の分解や異性化がみられず, 分析所要時間が最も短い。TCP ではp - メンタンの立体異性体の分離がなされた。squalaneはsqualeneよりも分離能悪く,β-ピネンの分解をともない4種の固定相のうち最も性能が悪いことを見出した。

数種の高純度テルペン炭化水素を調製し,これらの炭化水素類のガスクロマトグラムを7種の固定相について検討した。TCPおよびガスクロマトグラフの固定相として従来使用されていないsqualeneがすぐれた分離能を示すことを見出した。このうちTCPの方が分離能がよいがβ-ピネンを分解させる欠点がある。また両固定相について,各炭化水素と内部標準物質として用いた1,8-シネオールおよびシクロヘキサノールの試料量と保持時間との関係を決定して,試料量ゼロにおける各炭化水素の絶対的相対保持値を決定した。

Two homologous series of n-paraffins and sec-alcohols from C20 to C34 or C35 were isolated a wax constituents of a liverwort, Isotachis japonica. In both series, odd-members were predominant compared with even-members: the ratio of the total amount of odd- to total amounts of even-members was 3·9 in the n-paraffin homologues, and 16·5 in the sec-alcohol homologues.

During the course of investigation on constituents of liver-worts, four sesquiterpenoids showing opposite rotation, (−)-longiborneol, (−)-α-longipinene, (−)-longifolene and (+)-α-himachalene, were isolated from a Japanese liverwort. By preparation of derivatives and application of physical methods the absolute configuration of (−)-longiborneol, the main component, was elucidated as an optical antipode (I) of (+)-longiborneol isolated from higher plants.

Neutral constituents extracted from Metasequoia glyptostroboides HU et CHENG were investigated and seven steroids, β-sitosterol, stigmasterol, campesterol, stigmast-4-en-3-one, stigmasta-4, 22-dien-3-one, campest-4-en-3-one, and 5α-stigmastan-3, 6-dione, together with α-cadinol, m-cresol, and methyl esters of fourteen fatty acids, were identified. This is the first case that 5α-stigmastan-3, 6-dione, stigmasta-4, 22-dien-3-one, and campest-4-en-3-one were identified from natural products.