5-Deazaflavins and related compounds have been found to act as organic catalysts for the autorecycling oxidations of alcohols and amines to yield the corresponding carbonyl compounds in more than 100% yields. In particular, the pyridodipyrimidine derivatives (including bis-pyridodipyrimidines), which are structurally cyclized compounds of the amino analogues of Hantzsch esters and have a conjugated system similar to that of 5-deazaflavins, have shown outstanding oxidizing power toward a variety of alcohols to give the corresponding carbonyl compounds in astronomical yields based on the catalysts. On the other hand, it was found that 1, 5-dihydro-5-deazaflavins are able to reduce carbonyl compounds to the corresponding alcohols in stoichiometric yield in the presence of strong proton sources and that these reductions are automatically recycled in formic acid. The autorecycling reduction was further developed into the synthesis of α-amino acids and the selective reduction of α, β-unsaturated carbonyl compounds. The syntheses of several kinds of organic catalysts were included additionally in this review. The conception of autorecycling reactions by organic catalysts would be very significant from the viewpoints of resource saving and environmental preservation as well as synthetic organic chemistry.
The reaction of 2-bis (methylthio) methylene-1, 3-indadione with various active methylene compounds gave the corresponding displacement products of one methylthio group, some heterocyclic compounds (indeno [1, 2-b] pyridine, indeno [1, 2-b] pyran-2-one) and 9-fluorenone derivative in good results.
Sulfonyl ketenethioacetal, 2, 3-dihydro-2-bis (methylthio) methylene-3-oxobenzo [b] thiophene 1, 1-dioxide (3), was obtained by the reaction of 2, 3-dihydro-3-oxobenzo [b] thiophene 1, 1-dioxide (1) with carbon disulfide in the presence of sodium hydroxide in dimethyl sulfoxide, followed by treatment with methyl iodide. The reaction of 3 with various amines gave the corresponding amine derivatives and heterocyclic compounds (imidazoline, hexahydropyrimidine, oxazoline, benzimidazoline, quinazoline, and thiazoline). The reaction of 3 with active methylene compounds gave the displacement products (12a-c) of a methylthio group and the heterocyclic compounds, benzothieno [3, 2-b] pyridine derivatives (13a-c), in good yields. Similarly, the reaction of 3 with enamines afforded a good yield of corresponding compounds (17 and 18). The reaction of 3 with sodium cyanide in dimethyl sulfoxide gave 2-(1-cyano-1-methylthio) methylene-2, 3-dihydro-3-oxobenzo [b] thiophene 1, 1-dioxide (19) in good yield. The reaction of 19 with aniline or N, N-dimethylaniline also gave the corresponding displacement products (20 and 21) of methylthio group in good yields.
From the fronds of Wagneriopteris formosa LOEVE et LOEVE a new flavonol glycoside quercetin-3-O-β-D-alloside was isolated along with kaempferol-3-O-β-D-alloside. From the fronds of Woodsia polysticoides EATON a new flavonol acylglycoside kaempferol-3-O-α-L-(3"-O-acetyl) arabinofuranoside-7-O-α-L-rhamnopyranoside and its deacetylglycoside were isolated. Their structures were determined by chemical and spectroscopic methods.
A synthesis of 1, 1-(ethylenedioxy)-8a-methyl-Δ4a, 5-decalin (5) was achieved in three steps from the Wieland-Miescher ketone (1) and oxygenation reactions, namely, hydrobaration, epoxidation and osmilation, were investigated.
A series of 5-(3-aryloxypropyl)-1-cyclohexyltetrazoles was synthesized and tested for inhibitory activity towards collagen- and adenosinediphosphate-induced aggregation of rabbit blood platelet in vitro. These compounds were prepared by the reaction of 1-cyclohexyl-5-(3-iodopropyl)-tetrazole with phenols in the presence of a base. Among them, 6-[3-(1-cyclohexyl-5-tetrazolyl) propoxy]-1, 3-dihydro-1-ethyl-2H-benzimidazol-2-one (IVd) was found to have potent inhibitory activity. The structure-activity relationships are discussed.
Chemical constituents of the flower of Cammellia japonica, Theaceae were investigated. Three flavonols, quercetin, kaemferol and sexangularetin and three phenolic compounds, p-hydroxybenzoic acid, protocatechuic acid and gallic acid were identified. A sterol mixture of α-spinasterol and stigmast-7-en-3β-ol, and a glucoside mixture of stigmastry-D-glucoside and β-sitosteryl-D-glucoside were identified on the basis of spectral evidence and gas chromatography. A new triterpene, 3β-hydroxy-28-norolean-17-en-16-on-12, 13-epoxide was also identified on the basis of chemical and spectral data.
The saponin constituents in various kinds of soybeans : cultivated in several Prefectures in Japan, imported from U. S. A., Canada, and China, and black soybean cultivated in Hyogo Prefecture in Japan, have been investigated and soyasaponins I (1), II (2), III (3), A1 (4), and A2 (5) have been characterized from all kinds of soybeans. It has been found that soyasapoins in imported soybeans and black soybean are more or less acetylated and this makes the thin-layer chromatograms of soyasaponins from these soybeans rather complicated. In order to clarify the soyasaponin contents in various kinds of soybeans and soybean products, the quantitative analysis method for soyasaponins has been developed by means of gas-liquid chromatography.
Nicotineamide adenine dinucleotide phosphate-cytochrome P-450 reductase from porcine adrenal microsomes was purified to specific activity of 51.8 μmol/min/mg protein for cytochrome c reduction. The purified cytochrome P-450 reductase was a single protein band with a molecular weight of 78000±1000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The absorption spectrum of visible reagion showed peaks at 382 and 456 nm with a shoulder at 480 nm. The cytochrome P-450 reductase was capable of reconstituting 17α-hydroxylase, C17, 20 lyase and 21-hydroxylase activities in the presence of adrenal microsomal cytochromes P-450. It was noticed that 21-hydroxylase activity for 17α-hydroxyprogesterone was 1.3 fold higher than that for progesterone, and 17α-hydroxylase activity was 2.4 fold higher than C17, 20 lyase activity. The activity of 21-hydroxylase was 4-5 fold higher than 17α-hydroxylase activity when progesterone was used as a substrate. These activities catalyzed with cytochromes P-450 increased as a function of the amount of cytochrome P-450 reductase, and then these activities were saturated with P-450 reductase at the same ratio of reductase to P-450, i.e. 1 nmol of reductase/nmol of P-450.
The powers of ANOVA were calculated in the bioequivalence tests of diazepam tablets, flufenamic acid capsules, nalidixic acid tablets, griseofulvin tablets and cyclandelate capsules both in humans and beagle dogs. As measures of bioavailability, the peak serum (plasma) concentrations (the peak excretion rates) and the area under the serum concentration-time curves (the cumulative urinary excretion of drugs or metabolites) were more powerful than the peak time and the serum concentrations at each sampling time in the absorption phase in all drugs tested both in humans and beagle dogs. The estimated sizes of trials needed to detect 20% differences between the standard and test preparations tend to be larger in beagle dogs than in humans, especially in the trials of water-insoluble, neutral drugs such as griseofulvin and cyclandelate.
Three anhydrous forms (forms I, II, and III), dihydrate (form IV) and monoacetonate (form V) of carbamazepine were prepared and characterized by elemental analysis, infrared spectrum, X-ray powder diffraction, differential scanning calorimetry (DSC), and differential thermal analysis (DTA). The phase transition of these crystalline forms was investigated. Form I obtained by recrystallization from ethanol and form III obtained by drying form IV at 115°C under reduced pressure in P2O5 desicator, were very stable to moisture. Form II is relatively hygroscopic and when it was stored under 100% of relative humidity (R. H.) for 3 d, it was transformed to dihydrate (form IV) by absorbing 2 mol of water. Form IV was stable to moisture, when it was stored under 40-91% of R. H. at 37°C. But when it was stored under less than 32% of R. H. for 2 weeks, it lost 2 mol of water and was transformed to form III. Form V obtained by recrystallization from acetone was monoacetonate, and when it was stored under 100% of R. H. for 2 weeks, it lost acetone, absorbed 2 mol of water, and was transformed to form IV. Thermal analysis was also carried out for these crystalline forms and transition temperature, heat of transition, desolvation temperature, and heat of desolvation were measured by DSC and DTA.
Two derivatives of 5, 8-quinolinedione substituted with a hydroxyamino group were synthesized for the test of their antitumor activity. 7-(Hydroxyamino)-5, 8-quinolinedione was obtained by oxidation of 7-amino-5-imino-8 (5H)-quinolinone with hydrogen peroxide. 6-(Hydroxyamino)-5, 8-quinolinedione was synthesized from 6-amino-8-imino-5 (8H)-quinolinone, which was prepared from 6, 8-diamino-5-hydroxyquinoline obtained by reduction of the corresponding dinitro derivative.
Two steroidal components, Sj-1 and Sj-2 were obtained from the leaves of Solanum japonense NAKAI and characterized, respectively, as 3-O-β-lycotetraoside (1) of a mixture of solasodine and soladulcidine as aglycone and a furostanol glycoside (2) corresponding to a mixture of desgalactotigonin and aspidistrin. In addition, from the berries of this plant, Sj-2 and Sj-3 were obtained and the latter was identified as solamargine (3).
High performance liquid chromatographic method for the determination of scopolamine hydrobromide in seasick remedies was developed. Scopolamine hydrobromide in commercial products was extracted with chloroform, separated on an octadecylsilane column with a mixture of methanol and water (50 : 50, pH 4.0 with acetic acid) containing 5 mM sodium 1-heptanesulfonate as a mobile phase and detected at 215 nm. The detection limit was 0.15 μg and the recoveries from model preparations were 96.3% for powder form and 99.4% for lemonade.