Structure activity relationship of ar-turmerone analogues

For the analysis of structure activity relationship of ar-turmerone analogues, the compounds containing the various substituents on the phenyl ring and 1(or 2)-naphthyl group in the place of phenyl of ar-turmerone were prepared and tested their cytotoxicity against HL-60, K-562, and L1210 leukemia cellsin vitro. The substituents at para position are methoxy, phenoxy, methyl, trifluoromethyl, fluoro, and chloro. Atmeta position methoxy, methyl, trifluoromethyl, or chloro groups and atortho position methoxy or chloro group were introduced. Against HL-60 and K-562 cells, ED₅₀ values of the analogues are ranged from 0.8 to 30.0 μg/ml. Against L1210 cell, these are located more than 20.0 μg/ml. However, 5-carboethoxy-2-methyl-6-(1-naphthyl)-2-octen-4-one (5n) possesses ED50 valuses 0.8, 2.1, 6.5 μg/ml against HL-60, K-562, L1210 cells, respectively. The electronic nature of the subsituents on phenyl ring of ar-turmerone dose not affect the biological activity. Therefore the flat structure of aromatic portion of ar-turmerone analogues is the more important factor for their activity rather than its electronic nature. The potentiation of the cytotoxicity with the enlargement of aromatic ring region also supports the importance of the plane structure of this area. The restriction of the single bond rotation between C-6 and aromatic ring through the introduction of substituents at theortho position of phenyl ring and the increment of size of alkyl group at C-6 position enhances the activity. Therefore the effective conformation should be the one having the orthogonal arrangement between the aromatic ring and the side chain.     

Antitumor activity of pedunculagin,one of the ellagitannin

As a part of trials to develop the antitumor agent from tannins isolated from plants, the antitumor activity of pedunculagin, an ellagitannin, isolated fromAlnus hirsuta var.microphylla-was examinedin vitro andin vivo. In vitro, the cytotoxicity was determined by 0.4% trypan blue dye exclusion method. Pedunculagin showed the dose-dependent cytotoxicity against human chronic myelogenous leukemia (K-562), human promyelocytic leukemia (HL-60), mouse lymphoid neoplasm (P388), mouse lymphocytic leukemia (L1210) and mouse sarcoma 180 (S 180) cell lines. ED₅₀ values (ED₅₀) of each cell line were 5.30, 0.92, 2.78, 9.35 and 1.38 μg/ml respectively. The most sensitive cell line was HL-60.In vivo, pedunculagin was administered to ICR mouse with the doses of 50 and 100 μg/kg intraperitoneally once at 20 days before S180 inoculation. Pedunculagin showed the antitumor activity and its T/C ratio (%) was 120.82% in the group of both concentrations.     

A cytotoxic constituent fromSophora flavescens

A cytotoxic constituent was isolated by bioassay-guided procedure from the roots ofSophora flavescens Aiton (Leguminosae). The constituent was identified as sophoraflavanone G (I) by means of chemical methods and in comparsion with spectral data of standard compound. The ED₅₀ values of constituent I were 0.78, 1.57, 2.14 and 8.59 μg/ml against A549, HeLa, K562 and L1210 cell lines respectively. ConstituentI exhibited highly cytotoxic activities against A 549, K562 and HeLa cells, but showed a mild activity (ED₅₀ value, 5 μg/ml) against L1210 cells. Among the tested cell lines, A549 cells were the most sensitive to constituentI.     

2-(1-Oxyalkyl)-1,4-dioxy-9,10-anthraquinones: Synthesis and evaluation of antitumor activity

Fourty eight derivatives of 2-(1-oxyalkyl)-1,4-dioxy-9,10-anthraquinone were synthesized, and their antitumor activity was evaluated. On the whole, 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinones (DHAQ=1,4-dihydroxy-9,10-anthraquinone) showed stronger cytotoxic activity againnst L1210 cells than 2-(1-hydroxyalkyl)-1,4-dimethoxy.-9,10-anthraquinones(DMAQ=1,4-dimethoxy-9,10-anthraquinone), implying that free hydroxy groups at C-1 and C-4 of the anthraquinone structure are necessary for the cytotoxic activity. The bioactivity of 2-(1-hydroxyalkyl)-DHAQ derivatives differed according to the size of alkyl group at C-1, while the elongation of alkyl group over 7 carbon atoms failed to enhance, the bioactivity, the derivatives possessing alkyl moiety of 1–6 carbon atoms showed an increase in the cytotoxicity and the antitumor activity in Sarcoma-180; 2-hydroxymethyl-DHAQ (ED₅₀, 15 μg/ml; T/C, 125%), 2-(1-hydroxyethyl)-DHAQ(1.9 μg/ml; 139.2%), 2-(1-hydroxypropyl)-DHAQ (7.2 μg/ml; 135.1%), 2-(1-hydroxybutyl)-DHAQ (10.2 μg/ml; 125.3%), 2-(1-hydroxypentyl)-DHAQ (23.7 μg/ml; 110.1%) and 2-(1-hydroxyhexyl)-DHAQ (58 μg/ml; 108%). Next, 2-(1-Hydroxyalkyl)-DHAQ derivatives were acetylated to produce 2-(1-acetoxyalkyl)-DHAQ analogues. Although the acetylation somewhat enhanced the cytotoxicity, but not the antitumor action. In addition, the presence of phenyl group at C-1' enhanced the cytotoxicity and the T/C value, compared to alkyl groups of same size; 2-(1-hydroxy-1-phenyl)-DHAQ (ED₅₀, 5.6 μg/ml; T/C., 137%).     

Anti-cell adhesive effect of phenylacetylshikonin analogues related to their cytotoxicity in A549 cells

An attempt to estabilish the relationship between anti-cell adhesive action of phenylacetylshikonin anallogues and their cytotoxicity against A549 cells was done. In the one hour incubation with A549 cells, alpha-methoxyphenylacetyl-(9), alpha-acetoxyphenylacetyl-(13), 3,4-methylen-edioxyphenylacetyl-(15) and 4-(N,N-dimethylamino)-phenylacetylshikonin (17) analogues showed a high anti-cell adhesive activity (IC(100) value, 4-8 mug/ml), while halophenylacetyl-and dimethoxy-or trimethoxyphenylacetyl analogues expressed no activity at 40 mug/ml, indicating that the presence of a bulky group at C'-alpha and a polar group at C-4 of phenylacetyl moiety may be important. A similar structure activity relationship exists for the 48 hr cytotoxocity (ED(50)) of phenylacetylshikonin analogues in A 549 cells, but not in either K562 or L1210 cells. Furthermore, the difference between IC(100) values for anti-cell adhesive activity and ED(50) values for cytotoxicity of potent compound in A549 cells was not so great (1.5 to 3 times). Based on these observations, it is proposed that the anti-cell adhesive action of phenylacetylshikonins might be responsible for their cytotoxicity in A549 cells.     

Recognition of pharmacophore of ar-turmerone for its anticancer activity

For the analysis of structure activity relationship of ar-turmerone analogues, the compounds containing the various substituents on the phenyl ring and 1(or 2)-naphthyl group in the place of phenyl of ar-turmerone were prepared and tested their cytotoxicity against HL-60, K-562, and L1210 leukemia cellsin vitro. The substituents at para position are methoxy, phenoxy, methyl, trifluoromethyl, fluoro, and chloro. Atmeta position methoxy, methyl, trifluoromethyl, or chloro groups and atortho position methoxy or chloro group were introduced. Against HL-60 and K-562 cells, ED₅₀ values of the analogues are ranged from 0.8 to 30.0 μg/ml. Against L1210 cell, these are located more than 20.0 μg/ml. However, 5-carboethoxy-2-methyl-6-(1-naphthyl)-2-octen-4-one (5n) possesses ED50 valuses 0.8, 2.1, 6.5 μg/ml against HL-60, K-562, L1210 cells, respectively. The electronic nature of the subsituents on phenyl ring of ar-turmerone dose not affect the biological activity. Therefore the flat structure of aromatic portion of ar-turmerone analogues is the more important factor for their activity rather than its electronic nature. The potentiation of the cytotoxicity with the enlargement of aromatic ring region also supports the importance of the plane structure of this area. The restriction of the single bond rotation between C-6 and aromatic ring through the introduction of substituents at theortho position of phenyl ring and the increment of size of alkyl group at C-6 position enhances the activity. Therefore the effective conformation should be the one having the orthogonal arrangement between the aromatic ring and the side chain.     

Acetylpanaxydol und Panaxydolchlorhydrin,zwei neue,gegen L1210-Zellen cytotoxische Polyine aus Koreanischem Ginseng

Acetylpanaxydol and Panaxydolchlorohydrin, Two New Poly-ynes from Korean Ginseng with Cytotoxic Activity against L1210 Cells Two new polyines showing good cytotoxic activity against L1210 cells were isolated from Korean ginseng root. These were 3-acetyloxy-9,10-epoxy-heptadec-1-en-4,6-diyne (acetylpanaxydol, ED₅₀= 0.52 μg/nl) and 10-chloro-3,9-dihydroxyherptadec-1-en-4,6-diyne(Panaxydolchlorohydrin, ED₅₀= 0.50 μg/ml).     

Antineopastic natural products and the analogues IV. Aurapten,the cytotoxic coumarin fromPoncirus trifoliata against L1210 cell

A cytotoxic coumarin against L1210 cell was isolated from the unripe fruit ofPoncirus trifoliata (ED₅₀=10.2 μg/ml). Its structure was identified as aurapten, 7-geranyloxycoumarin. Hydrolysis of the substance gave umbelliferone and geraniol. Only geraniol showed the cytotoxic activity (ED₅₀=6.5 μg/ml) while umbelliferone and its methyl or allyl derivatives were not active.     

Synthesis andin vitro cytotoxicity of cinnamaldehydes to human solid tumor cells

Cinnamaldehydes and related compounds were synthesized from various cinnamic acids based on the 2′-hydroxycinnamaldehyde isolated from the bark ofCinnamomum cassia Blume. The cytotoxicity to human solid tumor cells such as A549, SK-OV-3, SK-MEL-2, XF498 and HCT15 were measured. Cinnamic acid, cinnamates and cinnamyl alcohols did not show any cytotoxicity against the human tumor cells. Cinnamaldehydes and realted compounds were resistant to A549 cell line up to 15 μg/ml. In contrast, HCT15 and SK-MEL-2 cells were much sensitive to these cinnamaldehyde analogues which showed ED₅₀ values 0.63-8.1 μg/ml. Cytotoxicity of the saturated aldehydes was much weak compared to their unsaturated aldehydes. From these studies, it was found that the key functional group of the cinnamaldehyde-related compounds in the antitumor activity is the propenal group.     

Synthesis of steroidal nitrosoureas as antitumor activity

Steroidal nitrosoureas have been synthesized and their antitumor activity on L1210 cells was evaluated. N-(2-Chloroethyl)-N-nitrosocarbamoyl-3-aza-A-homo-5α-cholestane (5a) showed significantly low ED₅₀ value of 1.6μg/ml whose activity is equivalent to that of methyl-CCNU (ED₅₀=1.7mg/ml).     

A cytotoxic component from Angelicae Koreanae Radix against L1210 and HL-60 cells

A cytotoxic sesquiterpene against L1210 and HL-60 cells was isolated from Angelicae Koreanae Radix (buk-kang-hwal). The component was identified as bisabolangelone by means of chemical and physical methods. The ED₅₀ values of it were 1.20 μg/ml against L1210 cells and 2.30 μg/ml against HL-60 cells. Bisabolangelone was found in buk-kang-hwal but not in kang-hwal.     

Polyoxygenated flavones; Synthesis,cytotoxicities and antitumor activity against ICR mice carrying S-180 cells

Fifty two flavones were synthesized from polyoxygenated dibenzoylmethanes which were obtained by a modified Baker-Venkataraman rearrangement, of 2-benzoyl oxyacetophenones. The following flavones among then showed good cytotoxic activities against L1210 and HL-60 cells; 2′-benzyloxy-5-methoxyflavone [ED₅₀(L1210)=4.9 μg/ml) ED₅₀(HL-60)=3.1 μg/ml] 2′-benzyloxy-5,7-dimethoxyflavone (8.2 μg/ml, 5.0 μg/ml), 2′-benzyloxy-5,7,8-trimethoxyflavone (5.9 μg/ml, 11.0 μg/ml), 2′-hydroxy-5,7-dimethoxyflavone (8.3 μg/ml 4.9 μg/ml) 2′-hydroxy-5-methoxyflavone (4.2 μg/ml, 2.7 μg/ml), 2′-hydroxy-5,7,8-trimethoxyflavone (9.8 μg/ml, 6.2 μg/ml), 2′-benzyloxy-5-hydroxyflavone (5.2 μg/ml, 3.6 μg/ml), and 5,2′-dihydroxyflavone (5.1 μg/ml, 4.0 μg/ml). Presence of 5-methoxy group potentiated the cytotoxic activity, while the existence of 7-methoxy group decreased the activity. 5-Hydroxy or methoxy, activates 4-carbonyl group, while 7-methoxy group deactivates the carbonyl group. From these observation it was concluded that the activation of carbonyl group at C-4 of a flavone is important for the enhancement of the cytotoxic activity. The presence of both 5-hydroxy and 2′-benzyloxy- or 2′-hydroxy group enhanced the antitumor activity; 2′-benzyloxy-5-hydroxy-7-methoxyflavone (T/C=144%), 5,2′-dihydroxy-7-methoxyflavone (T/C=132%), and 5,2′-dihydroxy-6,7,8,6′ tetramethoxyflavone (T/C=172%). 2′-Hexanoylation of 5,2′-dihydroxy-flavones did not improve the antitumor activity; 2′-hexanoyloxy-5-hydroxy-7-methoxyflavone showed T/C=132%, about the same as that of 5,2′-dihydroxy-7-methoxyflavone (T/C=130%)     

Studies on the mechanism of cytotoxicities of polyacetylenes against L1210 cell

This study was performed to investigate the mechanism ofin vitro cytotoxic actions of polyacetylenes which are panaxydol, panaxynol and panaxytriol isolated fromPanax ginseng C.A. Meyer. DNA synthesis of L1210 cells was significantly inhibited with dose-dependent pattern when L1210 cells were treated for 1 hour with over 5 μg/ml of polyacetylenes. Panaxydol which had the most potent cytotoxicity among three polyacetylenes showed also the strongest inhibitory effect on DNA synthesis. Intracellular cyclic AMP levels of L1210 cells treated with 2.5 μg/ml of panaxydol or panaxytriol were significantly elevated on the incubation duration. The elevation of cyclic AMP levels by panaxytriol was higher than that by panaxydol, but no significant increase in cyclic AMP by panaxynol was observed. All three polyacetylenes had no effect on glycolysis of L1210 cells. Electron microscopic observations revealed that polyacetylenes caused damage to plasma membranes of L1210 cells in proportion to their cytotoxicities at each ED₅₀ value (panaxydol>panaxynol>panaxytriol). These results suggest that cytotoxicities of polyacetylenes against L1210 cells might be mediated by elevated cyclic AMP level, even though the relationship among their cytotoxicities, inhibitory effect on DNA synthesis and ability to elevation of cyclic AMP level are not fully agreed, and might be also related to membrane damage.     

Antiviral, antitumor, and thymidylate synthetase inhibition studies of 5-substituted styryl derivatives of 2'-deoxyuridine and their 5'-phosphates

2′-Deoxyuridine derivatives containing styryl, 3-nitrostyryl, 4-nitrostyryl, and phenylethyl groups substituted at the 5-position of the pyrimidine ring have been evaluated for their effects on vaccinia and herpes simplex virus replication (in primary rabbit kidney cell cultures) and mouse leukemia L-1210 cell culture growth. 5-Phenylethyl-2′-deoxyuridine inhibited herpes simplex (type 1 and 2) virus-induced cytopathogenicity by 50 per cent at a dose (id₅₀) of 10–30 μg/ml. It was inactive against tumor cell growth. The corresponding styryl derivative showed an id₅₀ of 30–70 μg/ml for herpes simplex virus, 20 μg/ml for vaccinia virus, and 280 μg/ml for L-1210 cell growth. 5(E)-(3-Azidostyryl)-2′-deoxyuridine 5′-phosphate inhibited vaccinia replication with an IC₅₀ of 20 μg/ml and L-1210 cell culture growth with an id₅₀ of 80 μg/ml. The nucleotides of these compounds were all potent reversible inhibitors of thymidylate synthetase (Lactobacillus casei) with the following $\text{K}{}_{\mathrm{i}}\text{K}{}_{\mathrm{m}}$ ratios: 3-nitrostyryl, 0.035; 4-nitrostyryl, 0.05; 3-azidostyryl, 0.06; styryl, 0.08; and phenylethyl, 0.31. The photodecomposition of the azidostyryl derivative, a photoaffinity labeling reagent for thymidylate synthetase, was examined at two wavelengths.     

Cytotoxic Activities of Salvia. of the Labiatae Family

ABSTRACT

Eight crude extracts of five Salvia. species were evaluated for cytotoxic activities against brine shrimps and four human cancer cell lines [human colon adenocarcinoma (HCA), HepG2, MCF-7, and human pancreatic carcinoma (HPC) along with a normal mouse cell line (areolar cells)] as a control. In the brine shrimp lethality test, all samples, except S. fruticosa. L. (Sifnos collection) and S. verbenaca. L. (Zante collection), were found to be highly active with ED₅₀ values less than 300?μg/ml. In the case of human cancer cell lines, S. fruticosa., collected from Kalymnos and Crete, were active against HCA cells with LC₅₀?=?60.4 and 40.1?μg/ml respectively. Interestingly, only one sample, S. fruticosa. collected from Kalymnos, was active against HepG2 cells with LC₅₀?=?68.1?μg/ml. In the case of MCF-7 cells, S. fruticosa. collected from three different locations (Kalymnos, Rhodos, and Crete) showed similar activity with LC₅₀?=?43.1, 41.1, and 42.3?µg/ml, respectively. All S. fruticosa. samples were found to be cytotoxic toward a normal mouse cell line when tested at 0.1?mg/ml. All the other samples had LC₅₀ values greater than 75?µg/ml,and were considered to be inactive.     

New application of a stabilized active cyclophosphamide derivative (Mafosfamide,ASTA Z 7654) — immunogenic properties of lymphatic leukemia L 1210 cells treated in vitro with the drug

Lymphatic leukemia L 1210 cells were treated in vitro with various concentrations of Mafosfamide — a stabilized active derivative of cyclophosphamide (4-hydroxycyclophosphamide). L 1210 cells treated with Mafosfamide (L 1210-MAF cells) were used for vaccination of semisyngeneic CD2F₁ mice against L 1210 leukemia. These cells do not grow in vivo but are viable in the test with trypan blue. L 1210-MAF cells, obtained by treatment of L 1210 cells two times with 50 g/ml or 100 g/ml of Mafosfamide, and injected into the mice induced resistance against L 1210 leukemia in these animals. L 1210 cells treated two times with higher concentration of Mafosfamide (200 g/ml or 400 g/ml) did not give this effect.     

Inhibitory activity of diarylamidine derivatives on murine leukemia L1210 cell growth

Summary A series of 96 diarylamidine (and diarylimidazoline) derivatives were evaluated for their inhibitory effects on the growth and DNA synthesis of murine leukemia L1210 cells. The amidino- and imidazolino-substituted aryl moieties of the compounds consisted of phenyl, indole, indene, benzofuran, benzo[b]thiophene or benzimidazole. Several of these compounds were found to inhibit L1210 cell proliferation with an ID₅₀ (50% inhibitory dose) of 1 g/ml or lower. Structure-function analysis revealed that the antitumor cell activity of the diarylamidines depended on the planarity of the molecule, the presence of amidino- (or, preferably, imidazolino-) groups on both aryl moieties, the nature of the bridge connecting the two aryl moieties (preferably no bridge at all, phenoxy or ethene) and, finally, the nature of the aryl moieties (preferably, benzofuran or benzo[b]thiophene). Hence, compound 20 (6-(2-imidazolin-2-yl)-2-[4-(2-imidazolin-2-yl)phenyl] benzo[b]thiophene) emerged as the most potent inhibitor of L1210 cell growth (ID₅₀: 0.21 g/ml). Its inhibitory potency was similar to that of the well-known trypanocidal drug ethidium bromide (compound 98). For all diarylamidine derivatives taken together, some correlation (r = 0.612) was noted between the log ID₅₀ for L1210 cell proliferation and the log ID₅₀ for L1210 cell DNA synthesis (as monitored by [methyl ³H]dThd incorporation). These findings suggest that the inhibitory effects of the diarylamidines on L1210 cell proliferation may at least partially reside in an inhibition of DNA synthesis. Compound 41 (2,2-vinylenedi-1-benzofuran-5-carboxamidine), that exhibited a potent antitumor activity in vitro (ID₅₀: 1.5 g/ml), was further evaluated for its antitumor efficacy in vivo and found to increase the median survival time of L1210 cell-inoculated BDF₁ mice up to 204%, if administered at a dose of 200 mg/kg.     

Synthesis of benzo[c]phenanthridine derivatives and theirin vitro antitumor activities

Aiming at the development of anticancer agents by modification of phenolic benzo[c]phenanthridine alkaloid, additional hydroxyl group was put on C10 position of fagaridine (1) by a biomimetic synthetic procedure to afford 10-hydroxyfagaridine (12). All of the synthetic intermediates were also screenedin vitro antitumor activities against five different cell lines as well as12. Among them the representative cytotoxic results are shown as follows;p-quinone (11) [ED₅₀ (A549=0.22 μg/ml), (HCT15=0.21 μg/ml), fagaridine (1) (HCT 15=0.41 μg/ml), olefin (6) (HCT 15=0.06 μg/ml), acetal (7) (SKMEL-2=0.07 μg/ml), dihydrofagaridne (10) (A549=0. 38 μg/ml), 10-hydroxyfagaridine (12) (A 549=0.45 μg/ml). From these observation three main remarks can be drawn; (i) the iminium part of benzo[c]phenanthridine is not essential for showing acitvities, (ii) the additional hydroxyl group did not contribute to enhance the cytotoxicity, (iii) the 3-arylisoquinolin-1(2H)-one derivatives were found to display significantin vitro antitumor activity.