In addition to the known sex pheromone mimics of the American cockroach, (+)transverbenyl acetate [1 a], (+)-trans-verbenyl propionate [1 b] and (+)-verbanyl acetate [2 a], (+)-verbanyl propionate [1 b] was prepared. Eighteen of 25 m ales, of the cockroach, were sexually elicited by 0.02 mg of [1 b], which was most active among; the, mimics. Antipo des [(-)-isomers] of the mimics, [1' a], [1'b], [2' a] and [2' a], were synthesized to elucidate the chirality of the receptors for the mimics. A commercially obtained (-)-trans-verbenol was used for [1' a] and [1' b], whereas (-)-verbanol [9] synthesized in the present work for [2' a] and [2' b].
(+)-Apoverbenone [4] was converted into its antipode [4'] via [5] and [6]. [4'] was methylated to yield. (-)-trans-verbanone [7]. Meerwein-Ponndorf reduction of [7] affor ded. [9] with (+)-neoverbanol [8] (Scheme 1). Since no pheromonal activity was obse rved in any (-)-isomer: at the dosage of 0.3rng, the receptor for the mimics was elucidated to possess a chirality. This fact supports thechiral property of the sex pheromone, receptor of this insect which responds to an optical isomer of the sex pberomone, periplanone-B, but not to its an*pode.

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In order to determine the configuration at C-3, we synthesized both enantiomers of methyl 3-isopropylpentanoate isolated by 'Francke et al. as a unique degraded monoterpenoid pr obably responsible for the chemosensory communication among Formica species of ants. The carvone enantiomers were chosen as a starting material. Our products were shown to be∼100% opticalfy pure by the HPLC analysis of the amides obtained by treating the enantiomers of 3-isopropylpentanoyl chloride with (R) - (+) -1- (1-naphthyl)ethylamine.

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The acetone extract of fresh egg laying of Aplysia Kurodai was investigated first for the purpose of clarifying biologically active constituents. Two compounds, relatively predominant in the extract, were isolated. Their structures were established as chimyl alcohol (d-α-glyceryl hexadecyl ether) [1], mp 57°C, [α]_D +8.9°, and 5α, 8 α-epidioxycholest-6-en-3 β-ol [2], mp 153-154°C, [α]_D - 5.8°.

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One of the serious diseases of silkworm larvae reared on the artificial diets without antibiotics is the bacterial disease caused by abnormal multiplication of the intestinal bacteria, especially Streptococcus spp. However, the larvae fed on mulberry leaves under sanitary conditions are not practically attacked by the bacterial disease. This fact leadsto an idea that the antibacterial substances derived from mulberry leaves must control the growth of the pathogenic bacteria. in the midguts of larvae.
The authors have found that the digestive juice of the larvae contains 3, 4-dihydroxycinnamic acid (caffeic acid, CA), and that the concentration of CA is varied with starvation time. The concentrations, 460 and 222 ppm of CA in the juices starved for 1 and 2 h, respectively, were found to be enough to exhibit the antibacterial, activity. It has been clarified that CA is liberated from the reaction of chlorogenic acid (ChA) in mulberry leaves with an enzyme of the digestive juice in vitro. The authors found ChA in about O.35% of dry weight of the leaves by GLC or about 0.5% by TLC. In the culture medium of pH 10.0 CA showed remarkable inhibitory action at the level of 500 ppm against S. faecalis, while at pH 7.0, the same concentration was not effective in depressing the bacterial growth. It has been suggested that CA is converted into a real antibacterial substance, caffeoquinone, by base catalyzed oxidation in alkaline medium (pH 10.0). Synergistic actions between CA and ChA or CA and D-2, 3-diaminopropionic acid (DAPA) are discussed.

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Gonyautoxin-2 (GTX₂), a main component of paralytic shellfish poison, was isolated from the digestive glands (ay. toxicity: 400 MU/g) of toxic scallop Patinopecten yessoensis, by various types of chromatography using activated charcoal, Bio-Gel P-2, Amberlite CG-50, Sephadex G=15 and Bio-Rex 70. The preparation turned out homogeneous both in thin-layer chromatogrphy and in cellulose acetate membrane electrophoresis.
Instrumental analyses showed that the GTX₂ cont a ins the sulfur atom in the form of -OSO₃. Chemical shifts and spin-spin coupling constants of protons in ¹H-NMR of our GTX₂ agreed with those of 11-(OSO₃)saxitoxin isolated from the toxic scallop Pecten grandis by Schantz et al. The ¹³C-NMR spectrum of our GTX₂ was closely similar to that of 11- (OSO₃) saxitoxin as well as that of Protogonyaulax tamarensis GTX₂ isolated by Shimizu et al. These results support that GTX₂ has the structure of 11- (OSO₃)saxitoxin proposed by Schantz et al., and not that of 11- (OH)saxitoxin by Shimizu et al. The toxicity of our GTX₂ was estimated at 4200 MU/mg, being almost comparable to that of saxitoxin or tetrodotoxin.

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Potato cultivar “Rishiri” carrying the R1 gene is known to show a high level of resistance against the attack of Phytophthora infestans, and several antifungal substances defined as phytoalexins have been recognized to accumulate in tissues of the potato-tubers in response to the inoculation with P. infestans race 0, which is incompatible with the gene. Rishitin, one of such substances, is the major metabolite produced by this interaction and considered to play. an important role in the resistance to the pathogen. The present paper describes the metabolites produced newly by the interaction between the potato “Rishiri” and its compatible race of the pathogen. Whole tubers of “Rishiri” were wounded and inoculated with the race 1pathogen compatible with the R₁ gene and incubated for 18 days at 10°C. A careful chromatographic separation of the metabolites led to isolation of two unknown and nine known. compounds. Of the latter metabolites, three compounds, solavetivone, phytuberin and phytuberol, had not yet been detected in the interaction with the race 0 pathogen. Interestingly, the major phytoalexin was found to be solavetivone in the experiment. Since solavetivone has been considered to be an intermediate for the formation of rishitin, the present result suggests that the in vivo transformation of solavetivone into riphitin would be inhibited to some extent by P. infest anse with the race 1 gene. The new metabolites were identified as an 8-Oacetyl derivative of rishitinol and a 2-epimer of 10-epilubimin, on the spectroscopic and chemical grounds:

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In the course of our investigation on the terpenoids displaying plant growth-inhibiting properties from the liverworts (Hepaticae), four sesquiterpenoids were isolated from a le afy liverwort, Plagiochila ovalifOlia Mitt. and their structures were identified as (+)-ovalifolie ne [1], (+)-ovalifolienalone[2], (+)-ovalifolienal [3], and (+)-plagiochiline A [4]. The ent-2, 3-seco-alloaromadendranes [1], [2], [3], and [4] almost completely inhibited the growth of the rice seedlipgs at the concentrations of 25, 250, 50 and 50 ppm, respectively. The details of their growth-inhibitory effects are shown in Table 1 and 2.
Furthermore, the reaction products [5]∼[9] derived from (+)-ovalifo l iene [1] were also tested for the biological activity (see Table 1 and 2) in order to study relationship betw een the biological activity and the chemical structure. The results suggest that the in hibitory activity is due to the acetyl hemiacetal moeity. α-Methylene-δ-lactone [9] reveale d almost similar inhibitory activity to the natural inhibitors [1], [3], and [4] The ketone [2] and the γ-lactone C8D, however, promoted the growth of the root at the low concentration.

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Two main tannins have been isolated from the leaf of a Japanese medicinal plant, Mallotus japonicus Muell. Arg. (Euphorbiaceae) used for gastric ulcer. One was identified with geraniin which is the main tannin of Geranium species. The other one, mallotusinic acid, was obtained as yellow amorphous powder, C₄₈H₃₂O₃₂⋅xH₂O, and was found to be a new ellagitannin. Condensation with o-phenylenediamine gave a phenazine derivative, C₅₄H₃₄N₂O₂₉⋅y H₂O, which gave upon hydrolysis, “phenazine C”, a known hydrolysis product of “phenazine A” and “phenazine B” prepared from geraniin, and also the residual part of the original molecule, which was named mallotinic acid.
The struc ture of mallotinic adid was shown to be 1-galloy1-3, 6- (+)-valoneoy1-β-D-glucopyranose, by the results of hydrolysis of mallotinic acid and of methanolysis of methyl undecaO-methylmallotinate and methyl trideca-O-tnethylmallotinate, and also by the NMR and MS spectral data. Two carboxyl groups on the biphenyl ring of valoneic acid were assigned to form ester bonds with O-3 and O-6 of D-glucose in mallotinic acid.
These results together with the ¹H and ¹³C-NMR spectral da ta of mallotusinic acic and its derivatives indicate that mallotusinic acid has a dehydrohexahydroxybiphenyl-2, 2'-dicarbonyl group on 0-2 and 0-4 of D-glucopyranose of mallotinic acid. The dehydrohexahydroxybiphenyl2, 2'-dicarbonyl group in mallotusinic acid is always present as a mixture of the six-membered and five-membered hemiacetal structures.
Mallotinic acid was also detected in the extract of the leaf.

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In the preceding paper, the authors isolated an ovicide and a larval growth inhibitor from the benzene soluble fraction of the methanol extract of leaves of Eupatorium japonicum and identified them as coumarin and a new guaianolide named euponin [3] respectively. More precise fractionation (Fig 1) guided by Drosophila test of the benz ene soluble fraction led to the isolation of two larval growth inhibitors A and B.
Larval growth inhibitor A [1] was identified as the oxid ation product of euponin [3] by manganese dioxide through the analysis of their mp, MS, UV, IR and ¹H-NMR data. The structure of larval growth inhibitor B [2] was infered on the basis of spectral data and confirmed by chemical transformations shown in Fig.2.
Effects of [1], [2] and [3] on the development o f the fruitfly, Drosophila melanogaster were studied by administering them from the egg stage. The results are shown in Table 5. When the 1 st-instar larvae were introduced to the diet containing [2] they grew up normally to adults (Table 6). This indicates that like [3], [2] is not a feeding deterrent, and suggests that these sesquiterpene lactones inhibit the larval growth onyl when they are administered on the egg stage. The finding that a bioactive substance administered during embryonic stage has considerable influence on the growth or development in the succeeding stages would be important in understanding the defensive role of secondary substances of plants against herbivorous insects.

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The C₆-alcohols and -aldehydes such as cis-3-hexenol (leaf alcohol) etc. and trans-2-hexenal (leaf aldehyde) etc. are responsible for major characteristic odor of green lea ves of plants. We have demonstrated that the C₆-aldehydes are enzymatically produced from linolenic acid via 13-hydroperoxylinolenic acid formed by the oxygenation of linolenic acid and the C₆-alcohols are obtained by means of catalytic action of alcohol dehydrogenase in tea leaves.
This report describes the solubilization of the membrane-bound hydroperoxide lya se (E₂''), which catalyzes the cleavage of hydroperoxides to C₆-aldehydes, and the decomposition pathway from hydroperoxides to C₆-aldehydes. E₂'' enzyme activity was solubilized from tea chloroplast lamella membrane into 100000X g supernatant by the treatment with O.5 % (w/v) Tween 20. It was clarified that the formation of hexanal from 13-hydroperoxylinoleic acid was not proceeded via a-ketol ((Z)-13-hydroxy-12-oxo-9-octadecenoic acid).

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(2E, 6E, 10 Z)-3, 7-Diethyl-11-methyl-2, 6, 10-tridecatrien-1-ol (9-OH), (2E, 6E, 10Z)-3, 11dimethy1-7-ethy1-2, 6, 10-tridecatrien-1-ol (10-OH) and (2E, 6E, 10Z)-3, 7, 11-trimethyl-2, 6, 10tridecatrien-1-ol (3-OH), whose carbon skeletons were the same as those of insect juvenile hormones, JH 0, JH I and JH respectively, were synthesized enzymatically from (Z)-3methy1-2-pentenyl pyrophosphate (Z)-3-ethyl-3-butenyl pyrophosphat(4) and isopentenyl pyrophosphate (IPP) by the action of farnesyl pyrophosphate synthetase of pig liver. The occurrence of farnesyl pyrophosphate synthetase in Bombix moli (silk worm) was first demonstrated by the experiments with cellfree extracts. These results suggest that farnesyl pyrophosphate synthetase is involved in the biosynthesis of insect juvenile hormones.

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Avenalumins I, II and III were isolated as phytoalexins from oat leaves infected with the crown rust fungi, Puccinia coronata f. sp. avenae. Avenalumin I was characterized as 2-[2- (4hydroxyphenyl) e theny1]-6-hydroxy-4H-3, 1-benzoxazin-4-one, and the structure was confirmed by total synthesis. Phytopathological experiments suggested that avenalumins play an important role on the resistance of oat to the crown rust.

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About seventy 1, 3, 2-oxazaphospholidine derivatives were synthesized from α-amino acids according to the reaction scheme 2 or 3 and their insecticidal activity against houseflies was examined in comparison with some related heterocyclic phosphorus compounds. The insecticidal activity, of these cyclic phosphorus compounds was influenced by several factors as follows:
1) The ring size. Five-membered. ring was necessitated for the biological activities (Table 7).2) 4-Alkyl group or amino acid used. L-Leucine and L-valine gave highly insec ticidal derivatives (Tables 1 and 2).3) The configuration of the carbon atom at 4-position. D-Leucine gave the less active derivatives than L-leucine (Table 1).4) The exo-cyclic substituent on the phosphorus atom. The smaller the alkyl group, the higher the insecticidal activity.5) The position of an alkyl substituent. The 4-alkyl derivatives were better than the 3- or 5-alkyl derivatives (Table 3). Condensation of a benzene ring to the five-membered ring caused a great decrease in insecticidal activity (Table 5).6) The hetero atoms. Replacement of the oxygen atom in the hetero ring by a sulfur atom improved the insecticidal activity (Table 4).
Thus, (4S) - 4-isobuty1-2-methoxy-1, 3, 2-oxazaphospholidine 2-sulfide and the 4-isopropy l homolog were most promising as insecticides. They were particularly effective to control the organophosphate-resistant strains of houseflies (Table 6). Several 2-alkoxy-1, 3, 2-oxazaphospholidine 2-oxides inhibited acetylcholinesterase (AChE). The activity was also influenced by the exo-cyclic phosphorus substituent (Table 7). Oxazaphospholidine 2-sulfides were stabler than dioxaphosphole sulfides particularly under alkaline conditions, whereas the oxazaphospholidine was more active chemically rather than the dioxaphosphole in the 2-oxide analogs (Table 8). The distance between the phosphorus atom and the. h ydrophobic branched alkyl-cen ter is about 4.8Å in the leucine-derived cyclic phoiphoramidate. This is almost the same as the hypothetical distance between the esteratic site and the binding site of AChE. A hypothetical mechanism suggesting the importance of 4-alkyl group for AChE inhibition was proposed (Fig.1).

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Diterpenes which have a neoclerodane skeleton such as clerodin, clerodendrin A, and caryoptin show the absolute antifeeding activity for the larvae of Spodoptera litura F. and it is shown that the perhydrofuro[2, 3-b]furan ring in their structures is the active center of the antifeeding activity.
In order t o elucidate the structure-activity relationships of the antifeeding s ubstances, we synthesized the perhydrofuro[2, 3-b]furan derivatives with various phenyl substituents [5], [14], [23] and clerodin homolog [9]. As an approach to clarify quantitatively and rapidly structural factors (steric or electronic effects, etc.) which are essential for the appearance of biological activity of the model compounds, we considered the application of a chemical reaction on the active center, taking the place of their biological reactions on an receptor in vivo. Consequently, a good correlation came out between the chemical stability for mathanolysis of the model compounds by the steric control of their methyl groups and their biological activity. Based on these observations, we proposed the following hypotheses: i ) for the appearance of the biological activity, a definite steric environment around the active center is needed, ii)when the above condition is satisfied, the chemical reactions on the active center hold constant regardless of the supporting structures, the active center holding a constant reactivity represents a constant biological activity. This methodology discusses and compares the dynamic changes (reactivity) of the active center and the variation of biological activity as accompanied by structural changes, being conceptually termed “Dynamic Structure-Activity Relationships”.

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New synthetic methods for the preparation of isoxazolo[3, 4-d]pyrimidines and isothiazolo[5, 4-d]pyrimidines and their pharmacological activities were proposed.
6-Chloro-5-formyluracils [1] were treated with 2 equivalents of hydroxylamine to give the isoxazolo[3, 4-d]pyrimidines [6a∼f]. Compound [6a] was also synthesized by reaction of the oxime of [1] with an equivalent of hydroxylamine or by the Vilsmeier reaction of 6- (hydroxyamino)uracil [5]. The 3-substituted derivatives [4] and [6g∼j] were prepared by treatment of 6-chloro-5-cyanouracil [3] with hydroxylamine or by heating [5] in acid anhydrides. Isothiazolo[5, 4-d]pyrimidine. [11] was synthesized conveniently by the Vilsmeier reaction of 6-mercaptouracil [8] followed by the treatment with hydroxylamine. Compound [11] wa s also prepared by heating the oxime [2] with sodium hydrogensulfide. Some resulting compounds [6a, 6b, 6i, 11] showed an analgesic activity. Especially, [6 a] and [11] were about 6 times more active than aminopyrine.

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New sweet glycosides, rebaudiosides-A [3], -C [4] ( = dulcoside-B), -[5], -E[6] and dulcoside-A [7] have been isolated from leaves of Stevia rebaudiana Bertoni (Compositae)along with a known major principle, stevioside [1]. For the purpose of synthesis of [3], [5] and [6] from [1] preparation of ester glycosides of 19-carboxyl group of steviol [2](common aglycon of these glycosides) and its homologues was investigated. Ester glycosid es of this type could not be obtained by the usual procedure used for preparation of β-glucosyl ester of ent-kaurenoic acid [9] owing to the steric interaction of the 13-hydroxyl group. Preparation of β-glucosyl ester of [2] was achieved by the orthoester procedure and by this procedure [3] was prepared from [1] through the benzylidene derivative [20] of 13-O-β-glucosylsteviol [15] which was obtained from [1] by the enzymic partial hydrolysis followed by the alkaline saponification.
The β-glucobi osyl esters such as β-sophorosyl, β-cellobiosyl and β-maltosyl esters were obtained by the condensation with the corresponding cv-acetobromo sugar in the presence of silver carbonate on celite. By means of this procedure [5] and [6] were prepared respectively from [3] through [8] and from [1] through [18].
By the enzymic transglycosylation to [1] and [18], a series of a-glucosyl homologues, [21], [22] and [23] from [18]; [24] (a mixture of [24-1 and 2]), [25] (a mixture of [25-1, 2 and 3]) and [26] (a mixture of [26-1, 2, 3 and 4]) from [1] were stereo- and regioselectively prepared. For all of these natural and synthetic glycosides and the glycosid es of ent-kaurenoic acid derivatives isolated from Stevia paniculata and S. ovata; panicu losides-I, 11, N and V [27, 28, 29, 30 and 31] the structure-sweetness relationsh ip was investigated. It was disclosed that both 19-COO-glycosyl or -COOH and 13-O-glycosyl or -OH groups are essential for the revelation of sweetness of the glycosides of this type. It was also demonstrated that [3] and [5] having a branched sugar moiety exhibit the sweetest taste among the glycosides studied. Hydrogenation of 16 (17)-double bond led to a remarkable decrease of sweetness.

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As a continuation of our effort to identify the flavor constituents of Shoyu by means of the GC and GC-MS techniques, we have carried out the isolation and identification of compounds in the top note aroma of freshly heated Shoyu. Some of the identified compounds responsible for this aroma were subjected to the quantitative analysis. Shoyu flavor volatiles were isolated by using the methods; ( 1 ) vaccum co-distillation with water followed by freeze concentration and fractionation by preparative gas chromatography, ; ( 2 ) condensation of headspace volatiles given off during sweeping with pure helium gas followed by solvent extraction. The fractionated condensed volatiles were analyzed by GC-MS fitted with packed and glass capillary columns.
Fifty-four compounds were identified (Table 5). Among them, 6 compounds i. e. allyl alcohol, furan, 2-methylfuran, methyl acetate, ethyl 2-methylbutanoate and 1, 1-diethozy-2methylbutane were detected for the first time as Shoyu flavor constituents. Additionally, the major 14 compounds of these constituents were quantitatively determined by direct gas chromatographic analysis of headspace vapors (Table 2) and discussed with respect to the top note aroma of Shoyu.

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The seventeen derivatives of (+)-griseofulvin [1] were prepared in order to determine the activity of inhibition of microtubule polymerization and the depolymerization activity of microtubule. [1] was chemically transformed to afford its eleven derivatives: [5] [6], and [10] to [18]. Three 6-alkoxy derivatives: [7], [8] and [9] were prepared by the al kylation of 6-demethylgriseofulvin, which was obtained as a metabolite in the urine of rabbits following the administration of [1]. [2] was obtained from the broth of Penicillium urticae fermentation in the presence of potassium bromide. [3] and [4] were prepared from [2] by bromination. The partially purified microtubule proteins from pig brain were used for viscometric analyses. The activities of the test samples were shown as the percentage for the activity of [1], which was expressed as the decreasing ratio of the specific viscosity as cornpared with that of the control, in both experiments (Fig.3 and -Fig-.7). The correlation between the structure and activity was proved and the order of the activities was almost same in both experimental systems, except for isogriseofulvin [11] (Table 1). (-)-Gris'eofulvin [10], the enantiomer of natural (+)-griseofulvin [1], showed the very low activities in both the inhibition of microtubule polymerization and the depolymerization of microtubute. The activities of [1] were also confirmed by electron microscopy, in which samples, were negatively stained with uranyl acetate (Fig.4). Of eighteen samples tested, 3'-bromogriseofulvin [5] showed the highest activities. Accordingly, the aggregate-formation activity of [5] was compared with that of [1] whose activities are thoroughly examined. It was proved that [5] has weaker activity than that of [1] in the formation of aggregate of microtubule proteins at 4°C (Fig.8 and 9).

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In early sea urchin embryos, maternal messenger RNA synthesized during oogenesis plays a central role in translation. Protein synthesis occurs in the presence of inhibitors of RNA synthesis such as actinomycin D. The cleavage divisions require protein and DNA synthesis. On the other hand, starfish oocytes undergo meiotic maturational divisions in the presence of inhibitors of RNA and DNA synthesis. The maturational process is prevented by inhibitors of protein synthesis. Therefore, one can distinguish between inhibitors of RNA synthesis and those of protein synthesis by using sea urchin embryos and starfish oocytes.
Effects of pentopyranine C, i. e.1α-(3'-deoxy-L-arabinopyranosyl) cytosine were examined on mitotic divisions of sea urchin embryos and on meiotic maturational divisions of starfish oocytes. The only known action of pentopyranine C is to suppress the uridine incorporation into RNA in Ehrlich ascites cells. It was revealed that both cell divisions were susceptible to the drug application. Biochemical analyses using labeled nucleosideshave shown that pento- pyranine C dose not inhibit the biosynthesis of nucleic acids in sea urchin embryos although incorporation of the nucleosides into the cells is suppressed. Pentopyranine C inhibited protein synthesis in fertilized sea urchin eggs that had been preloaded with a labeled amino acid. Thus, the bioassay method as proposed in this study has been shown to be efficient in disting- uishing between inhibitors of RNA synthesis and those of protein synthesis.

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The stereospecific total synthesis of a 16-membered-ring lactone antibiotic A 26771 B [1] was pursued by using aldehyde [3] and Wittig reagent [9], both of which were derived from D-glucose, and Wittig reagent [6], which was from 1, 6-hexanediol. The Wittig reaction of [3] and [6] followed by deprotection, quantitatively yielded the unsaturated aldehyde [11], which was condensed with [9] to give the 16-carbon skeletal product [12]. Catalytic reduction of [12] afforded the saturated pentol [13], which, in turn, was converted into a properly masked product [14] by silylation followed by acetylation. Catalytic oxidation of the desilylated product followed by treatment with diazomethane gave the methyl ester [16]. Selective deacetylation of [16] accompanying the desired β-elimination gave the (E)unsaturated ester [17]. Acetonation of [17] followed by alkaline hydrolysis afforded the hydroxy acid [19], which was cyclized into the 16-membered-ring lactone [20] in a high yield. After the deacetonation of [20] a selective succinylation followed by oxidation gave the synthetic A 26771 B [1]. Identity of synthetic and natural products in all respects established the absolute stereochemistry to be 5, 9, 15R-configuration.

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(-)-Canadensolide, an antibiotic isolated from the culture of Penicillium canadense, was synthesized stereoselectively from D-glucose. The absolute configuration of (-)-canadensolide was determined unambiguously to be 2S, 3R, 4R-configuration by this study. The total yield of (-)-canadensolide from 1, 2: 5, 6-di-O-isopropylidene-α-D-glucofuranose was 7.1%.

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A simple synthetic method for macrocyclic ketones based on intramolecular alkylation of carbanion, generated from protected cyanohydrin is reported. Subsequent mild treatment with acid and base of the cyclized products leads to macrocyclic ketons in high yields. The reaction is rapid and irreversible, and hence required short reaction time The method was successfully applied to the synthesis of trans-2-cyclopentadecenone as a precursor of (±)-muscone and exaltone. As a synthetic target of keto lactones, the naturally occurring Zearalenone and the model compound of trans-resorcylide were synthesized.

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The synthesis and in vitro antibacterial activity of a new family of broad-spectrum cephalosporins [1] with increased stability toward β-lactamases are described. In the general, structure [1], aryl groups (R) and oxime O-substituents(R¹) in the oxyiminoacetyl side chain, and 3-substituents(R²) of a cephem nucleus are systematically changed in view of structureactivity relationships.
Cephalo sporins (Table 3∼6) with (Z)-2-(2-amino-4-thiazoly1)-2-(methoxyimino)acetyl side chain at the 7-position exhibit both superior potency against Gram-negative bacteria and broad spectrum of antibacterial activity. One of such cephalosporins, 7β-[(Z)-2-(2-amino-4-thiazoly1)2-(methoxyimino)acetamido]-3-cephem-4-carboxylic acid [7] was found to have an outstanding antibacterial profile, especially against Gram-negative bacteria, and its sodium salt (ceftizoxim. e as generic name) was selected as a clinical candidate.
Any modification (Table 7, 8) of the β-lactam nucleus resulted in the disappointed activity in the (Z)-2-(2-amino-4-thiazoly1)-2-(methoxyimino)acetyl series, and the cephem nucleus was found the most favorable in combination with this 7-acyl side chain.
In respect to chemistry, a number of the (oxyimino) acetic acids a nd cephalosporins (II, III, IV, V, VI) were prepared. Novel methods for the N-acylation of the 7β-amino group in the cephem nucleus and suitable protection of the 2-amino gruop in the thiazole ring were developed without isomerization of the syn oxyimino group.

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Structure-activity relationship among the diastereomers of an antifungal aminosugar antibiotic, prumycin [1] was studied. Among its seven possible diastereomers concerning the 2, 4-diamino sugar moiety, D-arabino-[2], D-ribo-[6], L-[7], and D-lyxo-prumycin [8] were newly prepared via the corresponding benzyl 4-azido-2-benzyloxycarbonylamino-2, 4-dideoxypentopyranosides followed by selective reduction of 4-azido group with Raney nickel, conde sation of N-benzyloxycarbonyl-D-alanine with dicyclohexylcarbodiimide and hydrogenolytic removal of the protecting groups. Antimicrobial activity of these diastereomers together with previously reported L-[3] and D-x yio-[4], and L-ribo-prumycin [5] was tested to prove that only [7] showed a moderate activity. Considering the ring structure and conformation determined by ¹H and ¹³C-NMR data, the importance of spacial rearrangement of 4- (D-alanylamino)and 2-amino groups for development of activity was indicated.

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In a synthetic endeavor to find out a general route to morphinandienones [3] via p-quinol acetates [7a], 8-chloro-p-quinol acetates [13a, b] have been prepared from 1-benzyl-8-chloro1, 2, 3, 4-tetrahydroisoquinolin-7-ols [12a, b] and subjected to acid treatment with trifluoroacetic acid giving the desired 8-chloromorphinandienones [14a, b] along with 9-chloroisopavines [15a, b] and 4β-hydroxyaporphines [17a, b]. An explanation for the unexpected formation of the latter two is presented.
Quite similarly, 8-chlorohomomorphinandienones [14c∼e], 9-chlorohomoisopavines [15c∼e], and 4β-hydroxyhomoaporphines [17c, d] have been obtained starting from the homologous p-quinol acetates [13c∼e]. Structure assignment of [17c] and [17d] has been based on the comparison of their diacetates with the authentic samples [18c and d], derived from monoacetates [19c and d], which have been afforded on lead tetraacetate oxidation of 1-hydroxyhomoa porphines [9a, b] respectively.
Finally, predominant formation of the desired homomorphinandienones [14c∼e] has been achieved by the oxidation of 8-chloro-1-phenethyl-1, 2, 3, 4-tetrahydroisoquinolin-7-ols[12c∼e] in a mixture of trifluoroacetic acid and acetic acid.

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17-Methoxy-D-homo-18-nor-5 a-androst-2, 13, 15, 17-tetraen-6-one [23] which has been derived from the product [24] resulting from the thermolysis of 1-[2-(1-cyano-4-methoxy-1, 2dihydrobenzocyclobuten - 1 - yl) - 1 - nitroethyl] -4, 4- ethylenedioxy - 2-methyl - 2- vinylcyclohexane [25] was converted into 1, 2, 3, 4, 4a α, 4 b, 5, 8, 8 aα, 9, 10, 10aβ-dodecahydro-2 α, 4 bβ-dimethyl-1β(3-pentynyl) -2β, 9β-phenanthrenediol [31], which gave 6β-hydroxy-5α-pregn-2-en-20-- one [32] on cyclization in acidic media. Jones' oxidation, followed by Prévost-Woodward re action of [31] resulted in the formation of 2β, 3β-diacetoxy-5 α-pregnane-6, 20-dione [34]. Finally, 2β, 3β, 20-triacetoxy-5α-pregnan-6-one [22] was derived from [34] by successive reduction, selective acetylation and Jones' oxidation. Since [22] has already been converted into 20-hydroxyecdysone, this work constitutes the formal total synthesis of 20-hydroxyecdysone.

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Warburganal [2] has been reported to have potent biological activities. Hoping to find out a less toxic and a more effective compound than [2], we intended the synthesis of a wide variety of the derivatives of [2]. In the course of this program, the total syntheses of (±)Cinnamodial [1] and (±)-Cinnamosmolide [3] having closely related structure to [2] have been accomplished starting from the allylic alcohol [7], an intermediate used in the synthesis of (±)-warburganai [2].
Since [1]is reported to be 6-β-acetoxy warburganal, the introduction of a keto group into the C-6 position. of [7] was initially investigated. This crucial step was achieved by the use of CrO₃-HOAc after protecting the side chain alcohol in [7] as a trichloroethoxycarbonyl derivative. The subsequent selective reduction of the α, β-unsaturated ketone [12] in the presence of base sensitive protecting groups was effected by using ether soluble and Almost neutral; Zn (13H₄)₂ Treatment of [13] thus produced with acetic anhydride in the presence of p-dim e, thyl-aminopyridine afforded the acetate [15]. The conversion of [15] into [1] was perf ormed in the same way as the preparation of [2] from [7]. The compound [15] was then converted to [3] by 1) Jones oxidation' to the carboxylic acid [17], 2) hydrolysis of the carbonate and simultaneous lactone formation, 3) reacetylation of C₆-hydroxyl group.

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Lewis acid (BF₃⋅OEt₂) mediated allylation of methoxy-p-benzoquinone [5] with trans-cinnamyltrimethyltin at low temperature and successive mild oxidation gives (±)-4-methoxydalbergione [3], an antibiotic, in high regioselectivity (77%) and good yield. The reaction system posesses the possibility of forrning six regioisomers, and the present synthetic method is the first successful example for the synthesis of [3] from the corresponding quinone [5]. Other Lewis acids (SnCl₄, AlCl₃) were ineffective for the reaction both in regioselectivity and in yield. The amount of BF₃⋅OEt₂ slightly affected the regioselectivity and the best selectivity was obtained when three equivalent of BF₃⋅OEt₂ was used. The selective coordination of BF₃⋅OEt₂ to MeO group of the quinone is proposed for the explanation of the high selectivity. This methodis suggested to be promising for the synthesis of important intermediates of versatile bioactive quinones.

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Preparation of new reagents disuccinimido carbonate (DSP) and succinimido diphenyl phosphate (SDPP) and their applications to the active ester synthesis are described. DSC was synthesized from N-hydroxysuccinimide (HOSu) and phosgene or trichloromethyl chlorof ormate as stable colorless prisms. DSC was further applicated to carbonyl insertion reactions and dehydration reactions. SDPP was synthesized from HOSu and diphenyl phosphorochlori-, date and was useful to the coupling reagent for peptide synthesis.

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Photo-cyclization of 5'-deoxy-5'- (phenylthio) guanosine 2', 3'-cyclic phosphate furnished 5'deoxy-8, 5'-cycloguanosine 2', 3'-cyclic phosphate, a fixed model of the anti-form of guanosine 2', 3'-cyclic phosphate. The UV an CD spectral behaviors of this cycloguanine nucleotide are essentially identical with those of guanylic acid. The cyclic phosphate was digestible with RNase T₁ to give 3'-phosphate. The spectral analysis of the interaction of RNase T₁ and the 8, 5'-cycloguanosine 3'-phosphate revealed that it behaved exactyl like 3'-guanylate. The previous assumption of interaction between RNase T₁ and guanosine 3'-phosphate of syn-form has now been revised, since the cycloguanine nucleotide should possess the anti-form. The corresponding adenine nucleotide was also synthesized.

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To elucidate the correlation between the structure and biological activity of 2'-substituted 2'-deoxypurinenucleoside derivatives, six ApA anologs containing 2'-fluoro-2'-deox yadenosine (dAfl) and 2'-chloro-2"-deoxyadenosine (dAcl) were synthesized and characterized by UV absorption, CD and ₁H-NMR spectroscopy. The dAfl derivatives have much higher population of C3'-endo puckering than adenosine in a furanose conformational equilibrium. The dAci derivatives have. similar C3'-endo population to that of adenosine. The experimental results suggest that the dAfl-containing dimers take a stacked conformation similar to that of ApA but with larger degree of stacking. The extent of stacking decreases in the following order: dAflpdAfl> dAflpi≈ ApdAfl> ApA. The dAcl-containin dimers take a stacked conformation similar %both in the mod6 and degree to 'that of ApA. These results show that C3'-endo puckering in both residues is required for optimum stacking in a ribo-dimer. The effects of 2'-substituents on polynucleotide conformation are di, scussed.

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2-Amino-3-(2-oxo-4-phenyl-1-azetidinyl)propionamide was synthesized as a model compound for the β-lactam moiety of bleomycin, of which the structure was proposed in 1972 b ut revised in 1978.
4 -Phenyl-2-azetidinone was N-hydroxymethylated with paraformaldehyde. The hydroxymethyl group was converted to the chloromethyl group with thionyl chloride. Condensation of thech loromethyl derivative and dimethyl (t-butoxycarbonylamino)malonate gave dimethyl 2- (tbutyloxycarbonylamino)2-(2-oxo-4-phenyl-1-azetidinylmethyl) malonate in 82% yield. One of the methoxycarbonyl groups was removed by alkaline hydrolysis followed by decarboxylation to afford a diastereomeric mixture of methyl 2- (t-butyloxycarbonylamino)-3-(2-oxo-4-phenyl1-azetidinyl)propionate in 74% yield. The diastereomeric mixture was separated by a silica-gel chromatography. Each diastereoisomer was ammonolyzed, followed by deprotection with trifluoroacetic acid to give the target substance.
One of the diastereoisomers of the target substance was crystallized as its hydrochloride from aqueous ethanol. The IR spectrum showed only one carbonyl absorption at 1710 cm-1, which is the least wave-number absorption in monocyclic β-lactams so far reported. The X-ray crystallographic study revealed that the relative configuration of the two asymmetric carbons is [S, S] or [R, R], the same as that of bleomycin, and the strong intra- and intermolecular hydrogen bondings cause such an abnormal IR absorption for the β-lactam.

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The graphic program for quantitative drug design (QDD) has been developed (Fig.1). This not only sets up the molecular models of candidates, but also allows to calculate their biological potencies, after establishing a regression equation for estimation of biological potencies both in the Hansch and the de novo analyses. Accordingly, it makes possible to promote efficiency in process of drug design to help visual understanding of the steric relation. This program only requires the Cartesian coordinates of constituent atoms of the parent molecule and the information on the equation etc. as the input data. The flows are controlled by function-key (FK) and alphabetical-numerical-key (ANK) operations. It allows easily to introduce the substituents in question to the parent molecule by the ANK operation, and promptly to display the perspective molecular figure of the resulting derivative on CRT, using NAMOD. It can also pursue the conformational change of molecule by rotating a particular atomic group around the single bond axis, and display the result of analysis if necessary. From the datafile, 337 kinds of substituents (Table 1) are available. For each substituent, 20 kinds of physicochemical parameter values (Table 2) and constituent atomic coordinates are stored. The substituent data are handled by the original input-code. Examples are shown in Fig.2 and 3 to illustrate the outline of the program. QDD is much improved as compared with the QSAR Programs which were reported previously. It is considered that QDD may be an interesting and useful tool for quantitative drug design studies.

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The field desorption (f. d.) technique which is a new ionization method allowing sample ionization without vaporization, can be effectively applied to the analysis of thermally labile or nonvolatile compounds.
The f. d. mas s spectra of various nonvolatile substances having a variety of chemical structures, mainly antibiotics, have been measured and the results of the structural study of natural products and the high resolution f. d. mass spectra are shown. From these data, it is clear that f. d. ionization method is a powerful technique in the structural study of nonvolatile bioactive substances, especially in determining the molecular weights of unmodified substances. In addition, fragment ions obtained at different emitter currents provide useful information.

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Reactions of trans- and cis-resorcylides ([1] and [2] respectively) with nucleophiles such as thiophenol, butylamine and imidazole, have been examined at room temperature. The olefinic double bond of the α, β-unsaturated ketone moiety was very reactive in [1], moderately reactive in the diacetates of [1] and [2] and did not react with these reagents in [2] The reactivities of [1], [2]and their diacetates were in parallel with their biological activi, ties (Table 1).

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Pellitorine [5] ( (2E, 4E)-N-isobuty1-2, 4-decadienamide) was synthesized from 1-heptyne [6] and methyl (E)-3-bromopropenoate [8] by a palladium catalysed stereospecific alkenylalkenyl cross-coupling reaction. This is a new facile synthetic method of pellitorine [5]. Fifteen amide analogues of pellitorine [12]∼[26] were also synthesized and their insecticidal activities against adzuki bean weevil (Callosobruchus chinensis L.) were reported.

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The presence of five sesquiterpenoid stress compounds, solavetivone, 3-hydroxysolavetivone, solanascone, phytuberin and phytuberol, were revealed in extracts from tobacco leaves infected with TMV. TMV, CMV and ethrel were effective elicitors to tobacco leaves. There were, however, differences in effect between viruses and ethrel. Viruses induced the accumulation of solavetivone and 3-hydroxysolavetivone, but ethrel induced phytuberin and phytuberol as major stress compounds.

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Herbimycin B is a new ansamycin antibiotic isolated from the cultured filtrate of Streptomyces hygroscopicus AM-3672. The antibiotic possesses potent herbicidal and anti-tabacco-mosaic virus activities. Herbimycin B, mp 229°C, C₂₈H₃₈N₂O₈, cntains a benzoquinone chromophore from the UV (λ_max 272 nm and 395 nm) and NMR (δc182.4, 187.8) spectral data. The structure was determined by means of the proton spin decoupling, long range ₁₃C [₁H] coupling and comparison of ₁₃C and 111 chemical shift values of herbimycin B with those of herbimycin A whose the structure has been established.

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Cotylenins and their aglycone, cotylenol [4] showed high germination-stimulating activity against lettuce seeds in the presence of abscisic acid. By the addition of DL-ethionine to the culture medium of the fungus at cotylenin-producing 'phase, new metabolites, cotylenin J [3] and [5, ] were isolated from the culture broth. The latter and its C₁₆-deoxy derivative had no such activity. Several derivatives of cotylenin E [1], [4] and [5] were prepared anctheir germination-stimulating activity was examined (Table 1). Structure-activity relationships in this assay were similar to those in the excised cotyledon assay.

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Agrobacterium tumefaciens is a widely distributed plant pathogen which induces crown gall tumors in a variety of plants, particularly in dicotyledonous plants. We extracted the cytokinin containing fraction from the culture medium of the virulent (plasmid-containing) strain (C 58) of the bacterium by the combination of 1-butanol extraction, ion-exchange chromatography, dry column chromatography packed with silica gel, thin-layer chromatography, high performance liquid chromatography, and betacyanin bioassay. From an eluate of the HPLC, we verified the presence of N⁶-isopentenyladenine by means of mass spectrometry.

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In the oxidation of benzylamine by molecular oxygen at 35°C and pH 9.2, 5-amino-6-hydroxyand 5, 6-diamino-2, 4 (1H, 3H)-pyrimidinediones were found to be efficient catalysts (Fig.1), while 5-amino-, 6-amino- and 5-acetylamino-6-amino-2, 4(1H, 3H)-pyrimidinediones, pyridoxal phosphate and pyridoxamine phosphate did not catalyze the oxidation. The yield of the oxidation product, identified as N-benzylidenebenzylamine, was almost quantitative (Table 1)on the basis of the quantity of oxygen absorbed. The absorption spectra of the catalyst (Fig.2) and the substrate specificity were discussed in relation to the amine oxidases.

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