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1.
Brain-corpora cardiaca-corpora allata complexes from the tobacco budworm Heliothis virescens produce both radiolabelled methyl (2E, 6E, 10Z)-10,11-epoxy-3, 11-dimethyl-7-ethyl-2, 6-tridecadienoate (JH I) and methyl (2E, 6E, 10Z)-10, 11-epoxy-3, 7, 11-trimethyl-2, 6-tridecadienoate (JH II) when cultured in medium containing L-[methyl14C] methionine or sodium [1−14C] propionate. Degradative studies of the hormones derived from propionate show the specific incorporation of the latter into the homo-isoprenoid portions of these compounds.  相似文献   

2.
In vitro organ cultures of corpora allata or corpora cardiaca-corpora allata complexes from Tenebrio molitor were found to produce methyl-(2E, 6E)-(10R)-10, 11- epoxy-3, 7, 11 trimethyl-2, 6-dodecadienoate (JH III). No detectable JH I or II was produced. The hormone was identified by derivation, chromatography and mass spectral analysis. A 14C radiolabel was incorporated into the methyl carbon of the ester function from precursor L-[methyl-14C]-methionine added to the culture medium.  相似文献   

3.
《Insect Biochemistry》1984,14(2):199-208
O-Pentafluorobenzyloxime (OPFB)-heptafluorobutyrylester (HFB) derivatives and OPFB-O-methyloxime (MO)-trimethylsilylether (TMS) derivatives of non-ecdysteroid steroids were prepared from haemolymph extracts of last instar larvae of the fleshfly Sarcophaga bullata. Using a negative ion chemical ionization capillary gas chromatography-mass spectrometry (NCI/GC-MS) technique the following steroids could be identified: progesterone, testosterone, 5α-androstane-3β,17β-diol, 5β-androstane-3α,17β-diol, androst-5-ene-3β,17β-diol, androstenedione, 5α-dihydrotestosterone, 11-ketotestosterone, 11β-hydroxytestosterone, 17α-hydroxyprogesterone, 17α-hydroxyprogesterone, 17α,20β-dihydroxyprogesterone. Although the technique is very sensitive, estrogens could not be detected. These results suggest an active metabolism of progesterone and testosterone.  相似文献   

4.
The conversion of a 5β-pregnan-3-one into a 3-thia-A-nor-pregnane is described. The single epimer, characterized as the 5β-isomer by nmr spectroscopy, was obtained.A previous report [1] from this laboratory described the synthesis of the epimeric 3-oxa-A-norpregnan-20-ones 1 and 2 from A-norprogesterone. Recently, the total synthesis of the related A-nor-3-thiaestra-1,-5(10)-diene derivative 3 has been described [2]. Continuing interest [3] in A-ring-modified steroids as probes of drug-receptor interactions prompts this report of the preparation of the 3-thia-5β-A-norpregnan-20-one 4.  相似文献   

5.
6.
A series of unsaturated and polyunsaturated fatty acids with a sulfur atom substituting for a methylene unit of the chain has been prepared and characterized. The syntheses were accomplished by the Wittig coupling of the ylid derived from the triphenylphosphonium salt of 9-bromononanoic acid with aldehydes containing sulfur. The newly formed double bond had predominately the natural Z geometry even when the starting aldehyde was conjugated with the sulfur atom. The sulfides 13-thia-9(Z)-octadecenoic acid (2), 13-thia-9(Z), 11(E)-octadecadienoic acid (5) and 13-thia-9(E), 11(E)-octadecadienoic acid (6) were readily converted into their sulfoxide derivatives by treatment with an equivalent amount of m-chloroperoxybenzoic acid. The structures of the novel compounds were confirmed by the application of ir, uv, 1H-nmr, 13C-nmr, and (as methyl esters) chemical ionization mass spectrometry. Two members of this new family of fatty acids (5 and 6) were found to inhibit the catalysis of the oxygenation of linoleic acid by soybean type-1 lipoxygenase. The analysis of the kinetic data for compound 5 indicated that the type of inhibition was reversible competitive with an inhibition constant of 30 μM.  相似文献   

7.
A third major chemical constituent of slow reacting substance (SRS-A) has been shown to possess the chemical structure 5(S)-hydroxy-6(R)S-cysteinyl-7,9-trans-11,14-cis-eicosatetraenoic acid (leukotriene E). Comparison of the biological activities of leukotriene E and the 11-trans stereoisomer on guinea pig airways, ileum, and cutaneous microvasculature has revealed a noteworthy dependence of activity on stereochemistry with leukotriene E being much more potent in each system.  相似文献   

8.
Steroids from starfish   总被引:2,自引:0,他引:2  
Y M Sheikh  M Kaisin  C Djerassi 《Steroids》1973,22(6):835-850
Starfish Linckia multifora, Protoreaster nodosus, Protoreaster lincki, Culcita schmideliana, Nardoa variolata and Acanthaster planci were examined for sterols and sapogenins. All asteroids contained cholestanol in addition to C27 to C30 mono and diunsaturated sterols. A planci contained largest amounts of 5α-cholesta-9(11), 20(22)-diene-3β, 6α-diol-23-one and 5α-pregn-9(11)-ene-3β,6α-diol-20-one whereas P. nodosus, P. lincki and C. schmideliana contained only small amounts. Neither pregnane nor cholestane genins were detected in L. Multifora and N. variolata.  相似文献   

9.
The physiological expression of a short-day-induced dormancy (Oligopause) of 4th-instar Chironomus plumosus larvae was investigated by measuring the oxygen consumption. By means of a polarographic continuous-flow respirometer the oxygen consumption of single larvae or groups of larvae (up to 5) could be measured continuously over a period of several hours. The oxygen consumption of dormant larvae is lower than in non-dormant larvae: in relation to the individual it is reduced by about 13, in relation to 1 g of dry weight by about 12. Dormant larvae are heavier than non-dormant larvae. In the dormant larvae, the proportion of dry weight to total weight is higher than in the non-dormant larvae. The increased proportion of dry weight is composed of a size-specific (dormancy-independent) and a dormancy-specific component. Independent of the sex and dormancy state, the larger larvae have a lower oxygen consumption per weight unit than the smaller larvae. A sex-specific difference can be observed: when animals with identical oxygen consumption per weight unit are compared, the females are considerably heavier than the males.  相似文献   

10.
The dinoflagellate Glenodiniumhallii was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol.  相似文献   

11.
More than thirty monohydroxy sterols were detected in the marine sponge Petrosia ficiformis, ranging from the ubiquitous 24-norcholesta-5, 22-dien-3β-o1 to the C30 sterol, 24-propylidenecholesterol. A new minor sterol was isolated and shown by spectral analysis and comparison with a synthetic sample to be (24R)-24,26-dimethy1cho1esta-5,26-dien-3β-o1 [26(29)-dehydroap1ysterol] (12).  相似文献   

12.
Methyl (2E, 6E) - 10, 11 - epoxy - 3, 7, 11 - trimethyl - 2, 6 - dodecadienoate (JH III) is synthesized by corpora cardiaca/allata of the American cockroach Periplaneta americana in vitro and released into the culture medium. It constitutes the principal part of the biologically detectable JH activity. A fully synthetic medium without terpenoid precursors or serum was used, which proves, that the entire molecule is synthesized de novo. The presence of JH III in orders as different as Blattodea, Orthoptera, Coleoptera and Lepidoptera indicates, that it is the most widely occuring JH of insects.  相似文献   

13.
A series of 12α-hydroxy steroids with varying side chains was prepared, and their 24-hour acetylation yields were compared, l2α-Hydroxy-5β-pregnan-20-one (lb) was prepared from 3α, 12α-diacetoxy-5β~pregnan-20-one (2) and also by side chain degradation of 12α-acetoxy-5β-cholanoic acid (5d). 21-Benzyl-5β-pregnan-12α-ol (1g) was synthesized by hydrogenation of the 21-benzylidine derivative of ketone 1b. 23-Pheny1-5β-norcholan-12α-ol (1k) was obtained by the Grignard reaction of 2-phenyl-ethylmagnesium bromide and ketone 1b, dehydration, hydrogenation and hydride reduction; a similar sequence produced 20-methyl-5β-pregnan-12α-ol (lm). The acetylation results (Table 11) imply that branching at C-20 may be more significant for 12α-hydroxyl reactivity than side chain length or type. An additional compound with an unbranched side chain, 21-nor-5β-cholan-12α-ol (14), was synthesized by a Grignard reaction on the 21-bromo intermediate 11b. Acetylation rates determined by glc indicate (Table 111) That compounds with unbranched side chains have 12α-hydroxyl groups about ten times as reactive as their analogs with 20-methyl groups.  相似文献   

14.
One juvenile hormone was isolated from culture medium containing isolated corpora allata of the grasshopper Schistocerca vaga (Orthoptera: Acrididae) and was shown by microchemical methods to be methyl (2E, 6E) - (10R) - 10, 11-epoxy-3, 7, 11-trimethyldodeca-2, 6-dienoate. This compound (JH III), which occurs in a sphingid moth Manduca sexta, is the first juvenile hormone identified in an insect order other than the Lepidoptera. Grasshopper organs incorporate both [2?14C] acetate and [methyl-14C] methionine into JH III showing de novo biosynthesis, but no indication of the synthesis of JH I or JH II was seen.  相似文献   

15.
A yellow pigment (C24H26N4PO15Na3) was isolated from Mycobacterium avium. On the acid hydrolysis the pigment (1 mol) gave L-glutamic acid (1 mol), lactic acid (1 mol) and 7,8-didemethyl-8-hydroxy-5-deazariboflavin-5′-phosphoric acid. The structure of N-[O-[[5-(8-hydroxypyrimidol[4,5-b]quinoline-10-yl-2,4(3H, 10H)-dione)-2,3,4-trihydroxypentyloxy]hydroxyphosphoryl]-L-lactyl]-L-glutamic acid was proposed for this compound. The compound isolated functions presumably as a new cofactor in a redox system of the bacteria.  相似文献   

16.
This report describes the in vivo metabolism of a new class of naturally occurring biologically active phospholipids (1-alkyl-2-acetyl-sn-glycero-3-phosphocholines) that can cause hypotension and platelet aggregation. After intravenous injection in male rats, the acetylated ether phospholipid (1-[1′,2′-3H]alkyl) is rapidly cleared (T12 ?30 s) from blood and its metabolites are found in a variety of tissues. The tissues containing the highest levels of radioactivity are lung, liver, spleen, and kidney. Chromatographic results showed that a considerable portion of the active lipid is not readily catabolized in some of the major tissues examined; however, inactive metabolites were also found, mainly 1-alkyl-2-lyso-sn-glycero-3-phosphocholine and 1-alkyl-2-acyl-sn-glycero-3-phosphocholine; the latter has a long chain fatty acid at the sn-2 position instead of the acetate. The findings are consistent with our earlier data that show these same tissues have the most active enzyme systems for metabolizing 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine.  相似文献   

17.
The nematode Trichinella spiralis is rejected from the intestine at a time that is characteristic for each inbred strain of mouse. Previous work (R. G. Bell et al. 1982a) had empirically identified strong, intermediate, and weak phenotypes (NFR, CHHe, and C5710 mice, respectively) in mice infected with 400 muscle larvae. It is shown that this classification applies to another eight inbred strains: SWR, DBA2, DBA1, LP, BubBn—all intermediate, and NZBBIN, C57L, A, and Mus molossinus—all weak. This phenotypic classification consistently applies with infections of 400–800 muscle larvae. Below doses of 300 muscle larvae, the strain designation of phenotype does not consistently apply. By this it is meant that the relative rejection rate changes for certain strains so that eventually some strains that were strong (NFR) or intermediate (AKR) responders to 400 muscle larvae become weak responders to 50 muscle larvae. Other strains increase their relative rejection time (B10 · BR, B10 · Q) while many do not change (NFS, C3HebFe, DBA2, DBA1). The phenomenon is most apparent in inbred parental strains rather than in F1 crosses, and it represents a phenotypic variation in rejection time that is dependent on dose. It is also demonstrated that time of rejection is directly proportional to dose in all inbred and F1 mouse strains that we have examined. Analysis of F1 crosses shows that most have the rejection time of the strongest responding parental line, suggesting simple genetic control of strong, intermediate, and weak responses. Two F1 crosses invalidated this theory. The DBA1 × C3HHe (intermediate × intermediate) showed a strong response. The additive effects of parental rejection phenotype indicated that these lines could not be genetically identical for intermediate responsiveness. Similarly, the NFR (strong) × B10 · BR (weak) F1 showed intermediate rejection, indicating partial dominance of C57B110 genes over the strong responder NFR strain. Neither the primary expulsion time phenotype, phenotypic variation to low doses, or the rejection characteristics of F1 crosses could be ascribed to genes linked to the major histocompatibility complex.  相似文献   

18.
Day 7 to 9 embryos were frozen by a rapid two-step method to ?38°C before being plunged into liquid nitrogen. Glycerol was used as the cryoprotectant and, following thawing, the embryos were cultured for 12 – 24 hours in PBS + 15% heat-treated steer serum. In Experiment 1, embryos were frozen in 2.0 ml glass ampoules or 0.5 ml Cassou straws. Two levels of glycerol (1.0M and 1.4M) gave comparable in vitro survival rates (1220 and 1325, respectively). A greater proportion of embryos developed in culture after freezing in straws. In Experiment 2, embryos were classified morphologically before and after freezing into 5 grades (1 = excellent; 2 = good; 3 = fair; 4 = poor; 5 = degenerate). Only embryos of grade 1, 2 and 3 were frozen. The post-thaw survival rates for embryos graded 1, 2 and 3 before freezing were 100% (1111), 86% (2428) and 83% (2024), respectively. Furthermore, the porportion of surviving embryos estimated to be of poor quality (grade 4) was greater for embryos graded 3 before freezing (1320) than for embryos graded 2 (624) or 1 (111). The percentage of embryos which developed normally after in vitro culture for each of the pre-freezing grades 1, 2 and 3 was 91% (1011), 50% (1428) and 29% (724), respectively. Of the total number of frozen-thawed embryos which developed in culture, 531 (16%) were of poor quality. The proportion of poor quality developing embryos was greater inembryos graded 3 before freezing (37) than those graded 2 (214). All of the embryos graded 1 before freezing and which developed in culture were of good quality. Results indicate that, if high post-thaw survival rates are to be obtained, stringent embryo selection processes will be required.  相似文献   

19.
The metabolic activation of benz(a)anthracene was investigated by incubating [3H]-benz(a)anthracene with DNA, a NADPH-generating system and rat-liver microsomes. When hydrolysates of the DNA were chromatographed on Sephadex LH20 columns, three hydrocarbon-nucleoside adduct peaks were resolved and these were further examined using HPLC. One adduct probably results from the reaction of the non-bay-region diol-epoxide r-8,t-9-dihydroxy-t-10,11-oxy-8,9,10,11-tetrahydrobenz(a)anthracene (anti-BA-8,9-diol 10,11-oxide) with DNA. The other two adducts did not co-chromatograph with adducts formed from any of the four possible isomeric diolepoxides that can be formed in the 8,9,10,11-ring of benz(a)anthracene.  相似文献   

20.
Recently, 1-β-D-arabinofuranosylcytosine-5′-diphosphate-DL-1,2-dipalmitin (VIa) was reported to inhibit the growth of L51784 cells in mice and of human colon carcinoma HCT-15 cells, also in mice. This paper describes the synthesis of a single diastereomer by conversion of 1-β-D-arabinofuranosylcytosine 5′-monophosphate (II) to the nucleoside 5′-phosphomorpholidate (III), followed by reaction with L-α-dipalmitoylphosphatidic acid (IV) to give 1-β-D-arabinofuranosylcytosine-5′-diphosphate-L-1,2-dipalmitin (V) in good yield. The separation of the product is described and its characterization by chromatography, elemental analysis, and spectroscopic methods. The lipophilic nature of V renders it insoluble in aqueous media and a method of sample preparation utilizing sonication techniques is described which provides a clear solution suitable for biological evaluation. In addition, the ability of V to inhibit the invitro growth of L1210 cells and of mouse myeloma MPC 11 cells is desscribed and compared with 1-β-D-arabinofuranosylcytosine (I) and other lipophilic prodrugs of I.  相似文献   

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