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1.
异香草醛经苄基化及Darzens反应制得3-苄氧基-4-甲氧基苯乙醛,用NaClO2/H2O2在异丙醇中氧化制得3-苄氧基-4-甲氧基苯乙酸,总收率72%。  相似文献   

2.
对羟基苯乙酮经硝化得到4-羟基-3-硝基苯乙酮,再在Na2CO3/KI作用下与氯苄进行O-烷基化反应后进行α-氯代得到4-苄氧基-3-硝基-α-氯代苯乙酮,总收率38%.  相似文献   

3.
目的寻找脂肪酸缩合酶Ⅲ(FabH)抑制剂1-(6-氯-3,4-亚甲-二氧基苄基)-2羧基-5-(2,6-二氯苄氧基)吲哚的新合成路线。方法以对乙酰氨基苯酚为起始原料,制备4-(2,6-二氯苄氧基)苯胺,用经典的Fischer吲哚合成法制备吲哚片断,随后引入6-氯-3,4-亚甲二氧基苄基,最后酯水解得到目标化合物。结果与结论目标化合物经1H-NMR1、3C-NMR和MS确证,中间体经1H-NMR确证。该路线成本低,操作简单可行,总收率14.2%,可顺利得到目标化合物。  相似文献   

4.
4-羟基-3-硝基苯乙酮经O-苄基化、溴化、还原制得1-(4-苄氧基-3-硝基苯基)-2-溴乙醇,然后酶促拆分得(R,R)-型福莫特罗的关键中间体(R)-1-(4-苄氧基-3-硝基苯基)-2-溴乙醇,总收率约25%.  相似文献   

5.
N-苄氧羰基-D-脯氨酸(2)经酰氯化反应制得N-苄氧羰基-D-脯氨酰氯(3),在三氯化铝催化下与5-溴吲哚经傅-克酰化反应制得(R)-3-(N-苄氧羰基吡咯烷-2-基甲酰基)-5-溴-1H-吲哚(5),再经二氢-双(2-甲氧基乙氧基)铝酸钠(SDMA)还原,得依立曲坦中间体(R)-5-溴-3-(N-甲基吡咯烷-2-基甲基)-1H-吲哚,总收率约41.5%(以2计).  相似文献   

6.
目的开发一条适合产业化的3-氯-4-(3-氟苄氧基)苯胺的合成工艺路线。方法以间氟氯苄和2-氯-4-硝基苯酚为原料,依次经碳酸钾存在下的缩合反应、铁粉/氯化铵还原得到3-氯-4-(3-氟苄氧基)苯胺。结果总收率为82%。所得产物经TLC、熔点和核磁共振氢谱表征,具有高纯度。结论本方法原料价廉易得,操作简便,环境污染更小,预期适合工业化生产。  相似文献   

7.
目的设计合成一系列6-苄氧基吲哚-2-甲酸糠醇酯衍生物,并测试其抗稻瘟霉菌活性。方法以4-羟基苯甲醛为原料,经O-苄基化、Knoevenagel反应、重排和水解反应得到6-苄氧基吲哚-2-甲酸(6),6与5-氯甲基糠醛反应得到6-苄氧基吲哚-2-甲酸-(5-甲酰基糠醇)酯(1),1分别经过还原、还原胺化和Knoevenagel反应得到相应的目标化合物。体外活性采用稻瘟霉菌筛选模型进行评价。结果与结论合成了13个新化合物,其结构经核磁共振氢谱、质谱确证,其中化合物1、8e、8f、8g的活性优于阳性对照灰黄霉素(griseofulvin)。  相似文献   

8.
目的合成4-苄氧基-3-硝基-α-溴代苯乙酮,并进行工艺改进。方法以对羟基苯乙酮为原料,经过硝化、苄基化、溴代三步反应合成得到4-苄氧基-3-硝基-α-溴代苯乙酮,总收率达到45.2%。结果合成产物经熔点、红外光谱、核磁共振谱等分析确定结构正确;与文献报道一致。结论与其他文献方法比较,该法具有操作简单、收率高、污染小、成本低等特点,并可用于工业生产。  相似文献   

9.
对羟基苯甲醛和2,6-二氯苄氯经O-烃化、Knoevenagel缩合、还原、C-烃化、水解脱羧反应得到具抗菌活性的2-(6-氯胡椒基)3-[4-(2,6-二氯苄氧基)苯基]丙酸.其中O-烃化在K2CO3作用下室温反应;Knoevenagel反应以三乙胺为催化剂、乙醇为溶剂,方便地获得中间体(Z)-3-[4-(2,6-二氯苄氧基)苯基]-2-氰基丙烯酸乙酯;还原反应中的原料和NaBH4为1:1摩尔量投料;总收率约65%(以对羟基苯甲醛计).  相似文献   

10.
用苄氧羰基氨基乙酸在N-甲基吗啉的催化下与氯甲酸异丁酯反应后,无需分离直接与氨基丙二酸二乙酯盐酸盐反应得到(2-苄氧羰基氨基乙酰胺基)丙二酸二乙酯,经Pd/C催化氢解、环合后在二氯甲烷中与Me3OBF4反应制得α-取代丝氨酸的合成中间体3,6-二甲氧基-2,5-二氢吡嗪-2-羧酸乙酯,总收率35.1%.  相似文献   

11.
Hexamethyldisiloxane (MM or HMDS) and decamethylcylclopentasiloxane (D(5)) are examples of a linear and a cyclic siloxane, respectively. These volatile low molecular weight siloxanes are of significant commercial importance. To aid in the pharmacokinetic investigations, major metabolites of MM and D(5) were identified in urine collected from Fischer (F-344) rats administered [(14)C]MM and [(14)C]D(5) orally and via intravenous injection. The metabolite profiles were obtained using a high-pressure liquid chromatography (HPLC) system equipped with a radioisotope detector. The metabolite elution was carried out on a C(18) column using an acetonitrile/water mobile phase. The structural assignments were based on GC-MS analysis of the tetrahydrofuran extract of urine containing the metabolites. Some of the metabolites in the extracts were first protected with trimethylsilyl groups prior to GC-MS analysis using bis(trimethylsiloxy)trifluoroacetamide or highly purified hexamethyldisiloxane. The structures were also confirmed by comparisons with synthetic (14)C-labeled metabolite standards. The following are among the major metabolites identified in the case of MM: Me(2)Si(OH)(2), HOMe(2)SiCH(2)OH, HOCH(2)Me(2)SiOSiMe(2)CH(2)OH, HOMe(2)SiOSiMe(2)CH(2)-OH, HOCH(2)Me(2)SiOSiMe(3), and Me(3)SiOH. The metabolites of D(5) are as follows: Me(2)Si(OH)(2), MeSi(OH)(3), MeSi(OH)(2)OSi(OH)(3), MeSi(OH)(2)OSi(OH)(2)Me, MeSi(OH)(2)OSi(OH)Me(2), Me(2)Si(OH)OSi(OH)Me(2), Me(2)Si(OH)OSiMe(2)OSi(OH)Me(2), nonamethylcyclopentasiloxanol, and hydroxymethylnonamethylcyclopentasiloxane. No parent MM or D(5) was present in urine The presence of certain metabolites such as HOMe(2)SiCH(2)OH and Me(2)Si(OH)(2) in MM and D(5), respectively, clearly established the occurrence of demethylation at the silicon-methyl bonds. Metabolites of the linear siloxane are structurally different from that obtained for cyclic siloxane except for the commonly present Me(2)Si(OH)(2). Mechanistic pathways for the formation of the metabolites were proposed.  相似文献   

12.
We describe the synthesis and some pharmacological properties of 16 new in vivo antagonists of oxytocin. These are based on modifications of three peptides: A, B, and C. A is our previously reported potent and selective antagonist of the vasopressor (V1 receptor) responses to arginine-vasopressin (AVP)/weak oxytocin antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid), 2-O-methyltyrosine]arginine-vasopressin (d(CH2)5[Tyr(Me)2]AVP. B reported here, the Ile3 analogue of A, is d(CH2)5[Tyr(Me)2]AVT (5 below) and C is our previously reported potent nonselective oxytocin antagonist/AVP V1 antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O- methyltyrosine,8-ornithine]vasotocin (d(CH2)5[Tyr(Me)2]OVT). The following substitutions and deletions, alone or in combination, were employed in A, B, and C: 1-deaminopenicillamine (dP); D-Tyr(Alk)2 (where Alk = Me or Et), D-Phe2; Val4, Thr4; delta 3-Pro7; Lys8, Cit8; desGly9, desGly-NH2(9), Ala-NH2(9); Leu-NH2(9); Arg-NH2(9). The 16 new analogues are (1) d(CH2)5[D-Tyr(Me)2]AVP, (2) d(CH2)5[D-Tyr(Me)2, Val4,delta 3-Pro7]AVP, (3) d(CH2)5[D-Tyr-(Et)2, Val4,Lys8]VP, (4) d(CH2)5[D-Tyr(Et)2,Val4,Cit8]VP, (5) d(CH2)5[Tyr(Me)2]AVT, (6) d(CH2)5[Tyr(Me)2,Lys8]VT, (7) dP[Tyr(Me)2]AVT, (8) dP[Tyr(Me)2,Val4]AVT, (9) d(CH2)5[D-Tyr(Me)2, Val4]AVT, (10) d(CH2)5[D-Phe2,Val4]AVT, (11) d(CH2)5[Tyr(Me)2,Thr4]OVT, (12) d(CH2)5[Tyr(Me)2,Thr4,Ala-NH2(9)]OVT, (13) d(CH2)5[Tyr(Me)2,Thr4,Leu-NH2(9)]OVT, (14) d(CH2)5[Tyr(Me)2,Thr4,Arg-NH2(9)]OVT, (15) desGly-NH2(9),d(CH2)5[Tyr(Me)2,Thr4]OVT, (16) desGly9,d(CH2)5[Tyr(Me)2,Thr4]OVT. 1-4 are analogues of A, 5-10 are analogues of B, and 11-16 are analogues of C. Their protected precursors were synthesized either entirely by the solid-phase method or by a combination of solid-phase and solution methods (1 + 8 or 8 + 1 couplings). All analogues were tested in rats for agonistic and antagonistic activities in oxytocic (in vitro, without and with Mg2+, and in vivo) assays as well as by antidiuretic and vasopressor assays. All analogues exhibit potent oxytocic antagonism in vitro and in vivo. With an in vitro pA2 (in the absence of Mg2+) = 9.12 +/- 0.09, dP[Tyr(Me)2]AVT is (7) one of the most potent in vitro oxytocin antagonists reported to date. Fifteen of these analogues (all but 6) appear as potent or more potent in vivo oxytocin antagonists than C (pA2 = 7.37 +/- 0.17). Analogues 1-9 and 14 are potent AVP V1 antagonists. Their anti-V1 pA2 values range from 7.92 to 8.45. They are thus nonselective oxytocin antagonists.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
We report the solid-phase synthesis of eight position-9-modified analogues of the potent V1-receptor antagonist of arginine-vasopressin, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O-methyltyrosine]arginine-vasopressin (d(CH2)5Tyr(Me)AVP) (1-8) and five position-9-modified analogues of the closely related beta,beta-dimethyl less potent V1 antagonist, [1-deaminopenicillamine,2-O-methyltyrosine]arginine-vasopressin (dPTyr(Me)AVP) (9-13). In d(CH2)5Tyr(Me)AVP the C-terminal Gly-NH2 was replaced by (1) ethylenediamine (Eda), (2) methylamine (NHMe), (3) Ala-NH2, (4) Val-NH2, (5) Arg-NH2, (6) Thr-NH2, (7) Gly-Eda, (8) Gly-N-butylamide (Gly-NH-Bu); in dPTyr(Me)AVP the C-terminal Gly-NH2 was replaced by (9) Ala-NH2, (10) Val-NH2, (11) Thr-NH2, (12) Arg-NH2, and (13) Tyr-NH2. All 13 analogues were tested for agonistic and antagonistic activities in in vivo rat vasopressor (V1-receptor) and rat antidiuretic (V2-receptor) assays. They exhibit no evident vasopressor agonism. All modifications in both antagonists were well-tolerated with excellent retention of V1 antagonism and striking enhancements in anti-V1/anti-V2 selectivity. With anti-V1 pA2 values of 8.75, 8.73, 8.86, and 8.78, four of the analogues of d-(CH2)5Tyr(Me)AVP (1-3 and 6) are equipotent with d(CH2)5Tyr(Me)AVP (anti-V1 pA2 = 8.62) but retain virtually none of the V2 agonism of d(CH2)5Tyr(Me)AVP. They are in fact weak V2 antagonists and strong V1 antagonists with greatly enhanced selectivity for V1 receptors relative to that of d(CH2)5Tyr(Me)AVP. With anti-V1 pA2 values respectively of 8.16, 8.05, 8.04, 8.52, and 8.25, all five analogues (9-13) of dPTyr(Me)AVP are at least as potent V1 antagonists as dPTyr(Me)AVP (pA2 = 7.96) and three of these (9, 12, 13) actually show enhanced V1 antagonism over that of dPTyr(Me)AVP. In fact, the Arg-NH2(9) analogue (12) is almost equipotent with d(CH2)5Tyr(Me)AVP. These new V1 antagonists are potentially useful as pharmacological tools for studies on the cardiovascular roles of AVP. Furthermore the analogues of dPTyr(Me)AVP may be useful in studies on the role(s) of AVP in the V1b-receptor-mediated release of ACTH from corticotrophs.  相似文献   

14.
Convenient and efficient methods were developed for preparing 1-(tetrahydro-2-furanyl)-5-fluorouracil (Thf-FU, 3) [trade name, Futraful (Ftorafur) or FT-207], which is used clinically as an antitumor agent, and 1,3-bis(tetrahydro-2-furanyl)-5-fluorouracil (Thf2-FU, 4). For the syntheses, 2,4-bis(trimethylsily)-5-fluorouracil (Me3Si-FU, 1) and 2-acetoxytetrahydrofuran (Thf-OAc, 2) were condensed in the presence of Friedel-Crafts catalysts, such as SnCl4 and BF3-Et2O in dichloromethane, or in the presence of NaI in acetonitrile to give Thf-Fu or Thf2-FU depending on the reaction conditions and workup procedure. A trace of 3-(tetrahydro-2-furanyl)-5-fluorouracil (3-Thf-FU, 5) was formed in these reactions. Thf2-FU was easily hydrolyzed to Thf-FU. 2-Methoxytetrahydrofuran can be used instead of Thf-OAc for preparation of Thf-FU under similar conditions. The optimal ratios of Me3Si-FU, Thf-OAc, and SnCl4 or NaI for preparation of Thf-FU and Thf2-FU were determined. In all cases, 2-2.5 equiv of Thf-OAc with respect to Me3Si-FU gave the best results. The yields of Thf-FU and more especially of Thf2-FU were greatly dependent on the relative amount of SnCl4, and 0.01-0.1 equiv of the catalyst with respect to Me3Si-FU gave the best results. Thf2-FU was found to be effective against murine solid tumors and it was less toxic than Thf-FU when given orally. The antitumor activity of 3-Thf-FU is also reported.  相似文献   

15.
Two vasopressin antagonists, d(CH2)5[Tyr(Me)2]AVP and dP[Tyr(Me)2]AVP, were given to Wistar rats from postnatal day 1 to 21 in order to investigate the influence on development and later diuresis. The latter antagonist significantly reduced body growth from day 3 postnatally onwards. At postnatal day 35 body, total brain, cerebellar and kidney weights were significantly reduced compared with controls. Diuresis, measured at one month of age, was four- to five-fold higher than the control group. Combined treatment with vasopressin failed to abolish the weight disturbances or polyuria. However, animals treated with the vasopressin antagonist d(CH2)5[Tyr(Me)2]AVP did not show developmental or diuretic deficits. Allometric analysis of brain/body relationship of the young animals indicated a disturbance of brain development by dP[Tyr(Me)2]AVP. Although the body and brain growth retardation induced by dP[Tyr(Me)2]AVP supports the hypothesis of a role for vasopressin in brain ontogeny, it can also be the result of a nonAVP-related toxic effect, since it could not be prevented by concomitant treatment with vasopressin.  相似文献   

16.
Many N,N‐dialkylated tryptamines show psychoactive properties and were encountered as new psychoactive substances. The aims of the presented work were to study the phase I and II metabolism and the detectability in standard urine screening approaches (SUSA) of 5‐methoxy‐2‐methyl‐N,N‐diallyltryptamine (5‐MeO‐2‐Me‐DALT), 5‐methoxy‐2‐methyl‐N‐allyl‐N‐cyclohexyltryptamine (5‐MeO‐2‐Me‐ALCHT), and 5‐methoxy‐2‐methyl‐N,N‐diisopropyltryptamine (5‐MeO‐2‐Me‐DIPT) using gas chromatography–mass spectrometry (GC–MS), liquid chromatography coupled with multistage accurate mass spectrometry (LC–MSn), and liquid chromatography‐high‐resolution tandem mass spectrometry (LC‐HR‐MS/MS). For metabolism studies, urine was collected over a 24 h period after administration of the compounds to male Wistar rats at 20 mg/kg body weight (BW). Phase I and II metabolites were identified after urine precipitation with acetonitrile by LC‐HR‐MS/MS. 5‐MeO‐2‐Me‐DALT (24 phase I and 12 phase II metabolites), 5‐MeO‐2‐Me‐ALCHT (24 phase I and 14 phase II metabolites), and 5‐MeO‐2‐Me‐DIPT (20 phase I and 11 phase II metabolites) were mainly metabolized by O‐demethylation, hydroxylation, N‐dealkylation, and combinations of them as well as by glucuronidation and sulfation of phase I metabolites. Incubations with mixtures of pooled human liver microsomes and cytosols (pHLM and pHLC) confirmed that the main metabolic reactions in humans and rats might be identical. Furthermore, initial CYP activity screenings revealed that CYP1A2, CYP2C19, CYP2D6, and CYP3A4 were involved in hydroxylation, CYP2C19 and CYP2D6 in O‐demethylation, and CYP2C19, CYP2D6, and CYP3A4 in N‐dealkylation. For SUSAs, GC–MS, LC‐MSn, and LC‐HR‐MS/MS were applied to rat urine samples after 1 or 0.1 mg/kg BW doses, respectively. In contrast to the GC–MS SUSA, both LC–MS SUSAs were able to detect an intake of 5‐MeO‐2‐Me‐ALCHT and 5‐MeO‐2‐Me‐DIPT via their metabolites following 1 mg/kg BW administrations and 5‐MeO‐2‐Me‐DALT following 0.1 mg/kg BW dosage. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

17.
1 The antiarrhythmic drug mexiletine (Mex) is also used against myotonia. Searching for a more efficient drug, a new compound (Me5) was synthesized substituting the methyl group on the chiral carbon atom of Mex by an isopropyl group. Effects of Me5 on Na+ channels were compared to those of Mex in rat skeletal muscle fibres using the cell-attached patch clamp method. 2 Me5 (10 microM) reduced the maximal sodium current (INa) by 29.7+/-4.4 % (n=6) at a frequency of stimulation of 0.3 Hz and 65.7+/-4.4 % (n=6) at 1 Hz. At same concentration (10 microM), Mex was incapable of producing any effect (n=3). Me5 also shifted the steady-state inactivation curves by -7. 9+/-0.9 mV (n=6) at 0.3 Hz and -12.2+/-1.0 mV (n=6) at 1 Hz. 3 In the presence of sea anemone toxin II (ATX; 5 microM), INa decayed more slowly and no longer to zero, providing a model of sodium channel myotonia. The effects of Me5 on peak INa were similar whatever ATX was present or not. Interestingly, Me5 did not modify the INa decay time constant nor the steady-state INa to peak INa ratio. 4 Analysis of ATX-induced late Na+ channel activity shows that Me5 did not affect mean open times and single-channel conductance, thus excluding open channel block property. 5 These results indicate that increasing hindrance on the chiral atom of Mex increases drug potency on wild-type and ATX-induced noninactivating INa and that Me5 might improve the prophylaxis of myotonia.  相似文献   

18.
Normal human lymphocytes (L) (8 X 10(5) ml-1) incubated with methoxamine (Me) (1 X 10(-7) M) (Me-L) triggered the mechanical response of the isolated vas deferens of the rat. L or Me alone did not modify this contractile activity at the concentrations cited above. Me alone (10(-6) to 10(-3) M) increased the tension of the vas. In the presence of L (8 X 10(5) ml-1) the dose-response curve to Me shifted to the left and the efficacy of Me was enhanced. Inhibitors of alpha 1-adrenoceptors completely blocked the reaction between Me and L while drugs that block alpha 1 and alpha 2-adrenoceptors reduced the reaction between Me-L and the vas deferens. Direct contact of Me-L with the assay organ was not necessary. Cell-free supernatants of L exposed to Me (Me-L supernatants) elicited the reaction in the same way as Me-L. This effect required the continuous presence of Me since dialyzed Me-L supernatants were inactive. Inhibitors of lipoxygenase(s) completely blocked the positive inotropic effect of Me-L or of Me-L supernatants. Inhibitors of cyclo-oxygenase potentiated this effect. These results suggest that Me reacts with alpha 1-adrenoceptors of L. From this reaction, soluble factors are released that potentiate the alpha-adrenoceptor stimulatory effect of Me on the vas deferens as a consequence of the release of oxidative products of the lipoxygenase/s pathway of arachidonic acid.  相似文献   

19.
1. Arginine vasopressin produced antinociception in the hot-plate test after intracerebroventricular injection (0.5 micrograms) and in the acetic acid abdominal constriction test after intraperitoneal injection (0.1 mg kg-1). 2. The antinociception produced by arginine vasopressin was sensitive to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms i.c.v.; 0.1 mg kg-1 i.p.) but not to naloxone (5 micrograms i.c.v.; 2 mg kg-1 i.p.) 3. Arginine vasopressin when administered by the intracerebroventricular route, but not by the intraperitoneal route, produced characteristic behaviour which was sensitive to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms, i.c.v.). 4. A 3 min swim at 20 degrees C produced antinociception on the hot-plate which was sensitive to naloxone (0.4 mg kg-1, i.p.) but not to deamino(CH2)5Tyr(Me) arginine vasopressin (0.5 micrograms, i.c.v.). 5. The reduction in the number of acetic acid-induced abdominal constrictions produced by a 30 s swim at 30 degrees C was not sensitive to either naloxone (2 mg kg-1, i.p.) or deamino(CH2)5Tyr(Me) arginine vasopressin (0.1 mg kg-1, i.p.). 6. Arginine vasopressin, at high doses, is antinociceptive in the mouse but does not appear to mediate stress-induced antinociception in this species.  相似文献   

20.
A group of alkane and alkanoic acid compounds of general formula MeS(O)m(CH2)nR [m = 0-2; n = 1, 5, 13; R = Me, CO2H(Na)] were synthesized for evaluation as cardiac inotropic and antifungal agents. Inotropic activity was determined as the ability of the test compound to modulate in vitro guinea pig atrium contractility. The oxidation state of the S-atom was an important determinant of inotropic modulation since the thio (m = 0) analogs exhibited a positive inotropic effect. In contrast, the sulfinyl (m = 1) and sulfonyl (m = 2) analogs exhibited a negative inotropic effect. A pentyl spacer (n = 5) provided the largest positive or negative inotropic effect. The relative positive, and negative, inotropic potency orders with respect to the R-substituent were Me > or = CO2H, and CO2Na > or = Me, respectively. The most potent positive inotrope MeS(CH2)5Me (EC50 = 4.49 x 10(-6) M) could serve as a useful lead-compound for the design of a new class of positive inotropic agents. In a broad spectrum antifungal screen, the minimal inhibitory concentration (MIC) range for the five most active compounds was MeSO2(CH2)5Me (0.46-1.83 mM), MeS(CH2)13Me (0.31-1.23 mM), MeSO(CH2)13Me (< 0.009-1.87 mM), MeSO2(CH2)13Me (0.27-1.09 mM), and MeS(CH2)13CO2H (0.27-1.09 mM), relative to the reference drug Ampotericin B (< 0.0002-0.002 mM). The most active antifungal agent MeSO(CH2)13Me was selective against C. guillermondi, C. neoformans, S. cerevisiae, and A. fumigatus (strain TIMM 1776).  相似文献   

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