Infliximab Ameliorates Methotrexate-Induced Nephrotoxicity in Experimental Rat Model: Impact on Oxidative Stress, Mitochondrial Biogenesis, Apoptotic and Autophagic Machineries

Accumulating data confirms that Methotrexate (MTX), a well-known immunosuppressive and anticancer drug, causes nephrotoxicity. Infliximab (INF), the inhibitor of tumor necrosis factor-alpha (TNF-α), was proven to have anti-inflammatory properties. Thus, it may have potential in preventing MTX-induced nephrotoxicity. Therefore, this study aimed to inspect the prospective nephroprotective effect of INF on MTX-induced rat nephrotoxicity through investigating the possible molecular mechanisms, including its interference with different death routes, oxidative stress as well as mitochondrial biogenesis. Rats received an INF intraperitoneal single dose of 7 mg/kg 72 h prior to a single 20 mg/kg MTX injection. MTX nephrotoxicity was demonstrated by significantly increased serum levels of the renal indicators urea and creatinine as well as renal inflammatory markers TNF-α and Interleukin-6 (IL-6) and the renal oxidative stress marker malondialdehyde (MDA), while renal antioxidant enzyme superoxide dismutase (SOD) was significantly decreased compared to control. INF injection prior to MTX markedly reversed these MTX-induced effects. Besides, MTX impaired mitochondrial biogenesis, while INF attenuated this impairment, as indicated by increased expression of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). Finally, MTX triggered apoptotic and autophagic cascades in renal tissues as evidenced by reduced anti-apoptotic Bcl-2 protein expression as well as elevated expression of the pro-apoptotic protein Bax and both key regulators of autophagy; beclin-1 and LC-3, whereas INF pretreatment counteracted these apoptotic and autophagic effects of MTX. Summarily, these results suggest that INF provides protection against MTX-induced nephrotoxicity which could be elucidated by its antioxidant, anti-inflammatory, anti-apoptotic and anti-autophagic effects as well as upregulating mitochondrial biogenesis.

The beneficial effects of l-carnitine and infliximab in methotrexate-induced hepatotoxicity: Emphasis on Notch1/Hes-1 signaling

Methotrexate (MTX)-induced hepatotoxicity is a serious adverse effect that may limit its use. Therefore, eligible drugs to ameliorate MTX-induced hepatotoxicity are required. l-Carnitine (LC) is a natural molecule with beneficial metabolic effects and infliximab (INF) is an anti-inflammatory monoclonal antibody against tumor necrosis factor-alpha (TNF-α). Recently, Notch1/Hes-1 signaling was found to play a key role in the pathogenesis of liver injury. However, its role in MTX-induced hepatotoxicity is unclear. This study aimed to evaluate the modulatory effects of LC or INF on MTX-induced hepatotoxicity and to explore the underlying mechanism with emphasis on the Notch1/Hes-1 signaling pathway. Sixty rats were randomized into six groups (n = 10): (1) control (saline); (2) MTX (20 mg/kg MTX, intraperitoneal [ip], once); (3) LC group (500 mg/kg ip, 5 days); (4) INF (7 mg/kg INF ip, once); (5) MTX+LC (20 mg/kg ip, once, 500 mg/kg ip, 5 days, respectively); (6) MTX+INF (20 mg/kg ip, once, 7 mg/kg INF ip, once, respectively). Oxidative stress, inflammatory markers, and Notch1/Hes-1 were investigated. MTX induced the expression of Notch1 and Hes-1 proteins and increased the levels of TNF-α, interleukin (IL)-6, and IL-1β in the liver. Cotreatment with LC or INF showed apparent antioxidant and anti-inflammatory effects. Interestingly, the downregulation of Notch1 and Hes-1 expression was more prominent in LC cotreatment as compared with INF. In conclusion, LC or INF attenuates MTX-induced hepatotoxicity through modulation of Notch1/Hes-1 signaling. The LC ameliorative effect against MTX-induced hepatotoxicity is significantly better than that of INF. Therefore, LC cotreatment may present a safe and therapeutically effective therapy in alleviating MTX-induced hepatotoxicity.

L-carnitine reverses methotrexate-induced nephrotoxicity in experimental rat model: Insight on SIRT1/PGC-1α/Nrf2/HO-1 axis

Methotrexate (MTX) is a chemotherapeutic agent used for treating several types of cancer as well as psoriasis and rheumatoid arthritis, but its use is limited due to its nephrotoxicity. The purpose of this research work was to observe ameliorative effects of L-carnitine (LC) toward renal toxicity caused by MTX and mechanisms responsible for these effects. Thirty-two male Sprague-Dawley rats were divided into four groups (eight rats/group), control group (received saline), MTX group (20 mg/kg/i.p. once), LC group (500 mg/kg/i.p. for 5 days), and MTX + LC group (received a single MTX dose 20 mg/kg/i.p. followed by LC 500 mg/kg/i.p. for 5 days). Histopathological examinations, lipid oxidation marker, malondialdehyde (MDA), and the antioxidant superoxide dismutase (SOD) as well as inflammatory (tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]) and apoptotic markers (Bax, Bcl2, and caspase-3) were used to assess renal toxicity. Moreover, the protein levels of silent information regulator 1 (SIRT1) and its downstream signaling targets, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), and nuclear factor erythroid 2-related factor 2 (Nrf2) in addition to heme oxygenase-1 (HO-1) were measured. LC significantly protected against MTX-induced nephrotoxicity. It ameliorated MTX-induced renal histopathological changes and diminished MTX-induced renal oxidative stress, renal inflammation, and apoptosis. LC also upregulated the expression of SIRT1 and PGC-1 as well as Nrf2 and HO-1. By controlling the expression of renal SIRT1/PGC-1/Nrf2/HO-1, LC displayed antioxidant, anti-inflammatory, and anti-apoptotic activities. Hence, using LC supplements may help prevent negative MTX side effects.

Golgi Signaling Proteins GOLPH3, MYO18A, PITPNC1 and RAB1B: Implications in Prognosis and Survival Outcomes of AML Patients

INTRODUCTION

The role of different Golgi signaling proteins remains unexplored in the progression and spread of Acute myeloid leukemia (AML), whom all interact together in a way that facilitates proliferation and differentiation of myeloid lineage cells.Material & methods: This study comprised 70 newly diagnosed AML patients and 20 healthy controls to investigate the serum levels of signaling proteins; Golgi Phosphoprotein 3 (GOLPH3), Myosin 18A (MYO18A), Cytoplasmic Phosphatidylinositol Transfer Protein 1 (PITPNC1), and Ras-Associated Binding Protein 1B (RAB1B).

RESULTS

AML patients showed higher serum levels of GOLPH3, MYO18A, PITPNC1, and RAB1B when compared to control (p < 0.001). A significant negative correlation was found between the patients' overall survival and GOLPH3 (p = 0.001), MYO18A (p = 0.011), PITPNC1 (p = 0.001), and RAB1B (p = 0.042). Results were confirmed by Kaplen-Meier survival analysis showing lower survival estimates in patients with higher GOLPH3 (p = 0.014), MYO18A (p = 0.047), PITPNC1 (p = 0.008) and RAB1B (p = 0.033) serum levels.

DISCUSSION

Golgi apparatus acts as master brain in membrane trafficking and signaling events that affect cell polarity necessary for migration, division, or differentiation. This study aims to explore the association between signaling proteins and the diagnosis, prognosis, and survival of AML patients.

CONCLUSION

GOLPH3, MYO18A, PITPNC1, and RAB1B maybe promising diagnostic and prognostic biomarkers in AML patients.

Antimicrobial, and Antibiofilm Activities of Silver Doped Hydroxyapatite: A Novel Bioceramic Material for Dental Filling

Even though hydroxyapatite (HA) is the most common biocompatible material; it has limited antibacterial resistance. HA experiences a tailor-made structure depending on the desired applications. In this regard, silver (Ag) is of particular interest to inhibit wide spectrum of pathogenic bacteria and other microorganisms. Silver doped hydroxyapatite (Ag-HA) was developed via wet co-precipitation with subsequent hydrothermal processing to hinder the growth and multiplication of pathogenic microbes. Ag-HA demonstrated mono-dispersed nano-rods of 70 nm length and 7 nm diameters. Even though silver dopant induced stresses within the crystal lattice; Ag-HA maintained the crystallographic structure of HA with no change. Ag-HA nanocomposite demonstrated Ca/P value of 1.238 compared with 1.402 for virgin HA via XPS spectroscopy. The reduction of Ca/P value was correlated to the partial replacement of Ca+2 with Ag+1; Silver content was reported to be of 1 atomic %. Elemental mapping using EDAX confirmed uniform dispersion of silver ion within HA lattice. Antimicrobial results indicated that, Ag-HA nanocomposite demonstrated the most potent zone of inhibition (ZOI) against Staphylococcus aureus, and Candida albicans. Antibiofilm results indicated that Ag-HA nanocomposite at 10.0 µg/mL, experienced the highest percentage for S. aureus and C. albicans of 96.09%, and 77.77%, respectively. Ag-HA nanocomposite demonstrated an excellent disinfectant agent once it had excited by UV light. In growth curve assay, the OD600 value of Ag- HA were lower, showing the repression impact on the growth of S. aureus. It was observed that the quantity of cellular protein discharged from S. aureus is directly proportional to the concentration of Ag-HA, which proves the antibacterial characteristics of the Ag-HA nanocomposite, and explains the creation of holes in the bacterial membrane producing the oozing out of the proteins from the S. aureus cytoplasm. Ag-HA nanocomposite achieved the complete lysis of the bacterial cell and cell malformation, decreasing the total viable number, so the outstanding antimicrobial results encouraged the tooth filling biomedical applications.

Graphical Abstract

Oxygen saturation measurements using novel diffused reflectance with hyperspectral imaging: Towards facile COVID-19 diagnosis

Oxygen saturation level plays a vital role in screening, diagnosis, and therapeutic assessment of disease's assortment. There is an urgent need to design and implement early detection devices and applications for the COVID-19 pandemic; this study reports on the development of customized, highly sensitive, non-invasive, non-contact diffused reflectance system coupled with hyperspectral imaging for mapping subcutaneous blood circulation depending on its oxygen saturation level. The forearm of 15 healthy adult male volunteers with age range of (20-38 years) were illuminated via a polychromatic light source of a spectrum range 400-980 nm. Each patient had been scanned five times to calculate the mean spectroscopic reflectance images using hyperspectral camera. The customized signal processing algorithm includes normalization and moving average filter for noise removal. Afterward, employing K-means clustering for image segmentation to assess the accuracy of blood oxygen saturation (SpO₂) levels. The reliability of the developed diffused reflectance system was verified with the ground truth technique, a standard pulse oximeter. Non-invasive, non-contact diffused reflectance spectrum demonstrated maximum signal variation at 610 nm according to SpO₂ level. Statistical analysis (mean, standard deviation) of diffused reflectance hyperspectral images at 610 nm offered precise calibrated measurements to the standard pulse oximeter. Diffused reflectance associated with hyperspectral imaging is a prospective technique to assist with phlebotomy and vascular approach. Additionally, it could permit future surgical or pharmacological intercessions that titrate or limit ischemic injury continuously. Furthermore, this technique could offer a fast reliable indication of SpO₂ levels for COVID-19 diagnosis.

The prospective prognostic value of the immune checkpoint BTLA expression in adult acute myeloid leukemia patients

Background

One of the crucial functions of the immune system is to prevent tumorigenesis, yet cancer occurs when malignant cells manage to evade immune surveillance via multiple strategies. Accordingly, this study aimed at assessing the potential significance of the novel immune checkpoint B and T lymphocyte attenuator (BTLA) as a prognostic marker in acute myeloid leukemia (AML), in addition to how it relates to response to treatment and patients’ survival. Thus, mRNA expression of BTLA was investigated on peripheral blood in 60 AML patients and 15 healthy controls.

Results

BTLA expression was found to be significantly elevated (p = 0.024) in the tested AML cases in comparison with healthy controls. Moreover, BTLA was over-expressed in the CD13, CD33, and HLA-DR positive cases as compared to their negative counterparts (p = 0.003; p < 0.001, and p = 0.001, respectively), and cases showing BTLA over-expression had significantly poorer overall survival times (p = 0.001) as confirmed by Kaplan–Meier survival analysis.

Conclusion

These observations suggest that BTLA over-expression may be associated with reduced immunity against tumors and could be recommended as a promising biomarker for unfavorable prognosis in AML.

Total RNA nonlinear polarization: towards facile early diagnosis of breast cancer

Different cancers are caused by accumulation of numerous genetic and epigenetic changes. Recently, nonlinear polarization has been considered as a marvelous tool for several medical applications. The capability of nonlinear polarization, to monitor any changes in RNA's spectral signature due to breast cancer (BC) was evaluated. Blood samples, from healthy controls and BC patients, were collected for whole blood preparation for genomic total RNA purification. Total RNA samples were stimulated with a light-emitting diode (LED) source of 565 nm; the resonance frequency of investigated RNA samples was captured and processed via hyperspectral imaging. Resonance frequency signatures were processed using fast Fourier transform in an attempt to differentiate between RNA (control) and RNA (BC) via frequency response. RNA (BC) demonstrated a characteristic signal at 0.02 GHz, as well as a phase shift at 0.031, and 0.070 GHZ from RNA (control). These features could offer early BC diagnosis. This is the first time to describe an optical methodology based on nonlinear polarization as a facile principle to distinguish and identify RNA alterations in BC by their characteristic fingerprint spectral signature.

Nonlinear polarization has been considered as a marvelous tool for several medical applications, and the capability to monitor any changes in RNA's spectral signature due to breast cancer was evaluated by hyperspectral camera.

Genetic signature of CTLA-4, BTLA, TIM-3 and LAG-3 molecular expression in colorectal cancer patients: Implications in diagnosis and survival outcomes

OBJECTIVE

Accumulating evidences suggest that immune checkpoints (ICs) inhibit immune response against cancerous cells and promote tumor cell survival. Up-regulation of ICs in tumor microenvironment is reported in patients with colorectal cancer (CRC). Thus, evaluating the peripheral blood expression of ICs may be used as non-invasive biomarkers for diagnosis and prognosis of CRC.

METHODS

This study included 60 primary and treatment naïve CRC patients along with 15 age and sex matched healthy volunteers as a control group. Total RNA was extracted from peripheral blood samples and gene expression of cytotoxic T lymphocyte antigen-4 (CTLA-4), B and T lymphocyte attenuator (BTLA), T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), and Lymphocyte activation gene-3 (LAG-3) was measured by quantitative real time polymerase chain reaction (qRT-PCR). All patients were followed for 12 months to correlate the measured ICs to patients' survival.

RESULTS

The gene expression of CTLA-4, BTLA, TIM-3 and LAG-3 was significantly up-regulated in CRC patients compared to the control group (p < 0.001). Individually, CTLA-4 and BTLA showed 85% sensitivity in discriminating CRC patients from control group (p < 0.001). On the other hand, TIM-3 and LAG-3 expression showed higher sensitivity (93%) for diagnosis of CRC (p < 0.001). Conversely, CTLA-4 or BTLA strongly predicted CRC patients' survival (p < 0.001) compared to TIM-3 (p = 0.018) or LAG-3 (p = 0.035). CTLA-4, BTLA, TIM-3 and LAG-3 were independent prognostic factors of survival after adjustment for age and gender.

CONCLUSION

The current study provided evidence that blood gene expression of ICs was up-regulated in CRC patients and associated with cancer stage and patients' survival, which highlights the diagnostic and prognostic values of ICs expression in CRC. Further investigations and validations in larger cohorts are required.

Expression of immune check point gene TIM-3 in patients newly diagnosed with acute myeloid leukemia: Significance and impact on outcome

Despite recent advancements in the therapeutic landscape of acute myeloid leukemia (AML), the prognosis of patients remains poor. Immune check point inhibitors have been investigated in hematological malignancies, including AML; however, the role of T-cell immunoglobulin and mucin domain 3 (TIM-3) in AML has not yet been fully elucidated. Thus, the present study aimed to investigate TIM-3 gene expression in patients with AML and determine its associations with prognostic variables and clinical outcome. A total of 60 patients newly diagnosed with AML and 15 healthy matching individuals were recruited in the present study, and reverse transcription-quantitative PCR analysis was performed to detect TIM-3 expression. The results demonstrated that TIM-3 expression was significantly upregulated in patients with AML compared with that in healthy individuals (P<0.001). In addition, patients with extramedullary disease (EMD) exhibited significantly lower median TIM-3 expression levels compared with those without EMD (P=0.001). Furthermore, patients with high TIM-3 expression had significantly lower complete remission rates following induction chemotherapy compared with those with low TIM-3 expression (P=0.004). High TIM-3 expression was significantly associated with lower overall survival rates during the 1-year follow-up (P=0.001). Taken together, the results of the present study suggest that TIM-3 may act as a biomarker of a poor prognosis in patients with AML, and be used as a therapeutic target.

Serum levels of FAK and some of its effectors in adult AML: correlation with prognostic factors and survival

Focal adhesion kinase (FAK), human myofibrillogenesis regulator-1 (MR-1), ephrin receptor type A4 (EphA4), proto-oncogene tyrosine kinase Src (Src), and protein kinase C (PKC) are important markers in proliferation, survival, and migration in some cancers. However, the significance of each is still unclear in different malignancies, including acute myeloid leukemia (AML). Therefore, this study was conducted to investigate their serum levels in Egyptian adult de novo AML patients (n = 70) against healthy volunteers (n = 20). We managed to study the correlation between each pair and to investigate their association with diagnosis, prognosis, and survival. Serum levels were analyzed using enzyme-linked immunosorbent assay (ELISA). We found that FAK, MR-1, Src, and PKC serum levels were significantly higher in AML patients compared to control (p < 0.0001), and this was associated with significantly lower EphA4 level (p < 0.0001). Interestingly, we also observed a significant negative correlation of FAK (p = 0.027), MR-1 (p = 0.003), Src (p = 0.038), and PKC (p = 0.03) with patients' overall survival (OS) while there was a positive significant correlation between EphA4 and OS (p = 0.007). In conclusion, this study suggests that FAK, MR-1, EphA4, Src, and PKC may be used as early diagnostic and prognostic markers with high sensitivity and specificity in AML patients and thus may be incorporated into the patients' early diagnostic and prognostic panels.

The immune checkpoints Cytotoxic T lymphocyte antigen-4 and Lymphocyte activation gene-3 expression is up-regulated in acute myeloid leukemia

One of the fundamental hallmarks of cancer is the incapacity of the immune system to eliminate malignancy. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) and lymphocyte activation gene-3 (LAG-3) are considered major inhibitory immune checkpoints expressed on T cells. In this study, we investigated mRNA expression of CTLA-4 and LAG-3, as well as their diagnostic and prognostic value in acute myeloid leukemia (AML) patients. The study involved 60 AML patients and 15 controls. Significantly up-regulated CTLA-4 (P = .005) and LAG-3 (P = .02) mRNA expressions were found in AML patients as compared with the healthy control group. AML patients with unfavorable prognosis also showed significant up-regulation of CTLA-4 (P = .006) and LAG-3 (P = .001) mRNA expressions as compared with those with favorable prognosis. Moreover, multiple stepwise linear regression analysis confirmed that patients prognosis was an independent predictor of both CTLA-4 (P = .003) and LAG-3 (P < .001) expression levels. Receiver-operating characteristic (ROC) curve using combined CTLA-4 and LAG-3 expression showed good diagnostic value for AML (area under the curve [AUC] = 0.80, sensitivity = 80%, specificity = 80% for a cut-off probability >.619) as well as moderate predictive value for unfavorable prognosis (AUC = 0.760, sensitivity = 70%, specificity =100% for a cut-off probability >.617). It is clear from this current study that both CTLA-4 and LAG-3 may be promising prognostic markers in AML patients.

Adipose Tissue-Derived Mesenchymal Stem Cells Protect Against Amiodarone-Induced Lung Injury in Rats

Pulmonary fibrosis (PF) is a progressive and irreversible lung disease, characterized by poor prognosis with limited treatment options. Mesenchymal stem cells (MSCs) are multi-potent cells having the ability to self-renew and differentiate into multiple tissues, thus considered a novel treatment option. The present study aimed to investigate the possible antifibrotic effect of undifferentiated adipose tissue-derived mesenchymal stem cell (AD-MSC) therapy on PF experimentally induced in rats using amiodarone (AMD). AMD (30 mg/kg) was given orally, once daily for 12 consecutive weeks to induce lung fibrosis. Following the confirmation of lung damage with histopathological examination, AD-MSCs (2 × 10⁶ and 4 × 10⁶ undifferentiated MSCs) were injected once intravenously, followed by 2 months for treatment. AMD induced focal fibroblastic cells proliferation in the peribronchiolar tissue, as well as in between the collapsed emphysematous alveoli. Also, AMD significantly increased serum and lung homogenate fibroblast growth factor-7 (FGF7), Clara cell protein-16 (CC16), and cytokeratin -19 (CK19) levels, as well as the expression of both iNOS and NFкB in the lung alveoli. Moreover, AMD caused excessive collagen deposition and increased alpha smooth muscle actin (α-SMA) expression. All findings significantly regressed on stem cell therapy in both doses, with superior effect of the high dose, providing evidence that adipose tissue-derived MSCs could be a promising approach for the treatment of PF. Graphical Abstract.

Beclin-1 and hypoxia-inducible factor-1α genes expression: Potential biomarkers in acute leukemia patients

BACKGROUND

Beclin-1, an important autophagic gene, and hypoxia-inducible factor-1α (HIF-1α), the master regulator of the hypoxic response, are reported in several human cancers. However, their expressions in acute leukemia haven't yet been well investigated.

OBJECTIVE

This study was designed to investigate the gene expression of beclin-1, microtubule-associated protein-1 light chain-3B (MAB1LC3B), the anti-apoptotic marker Bcl-2, and HIF-1α, as well as to evaluate the relationship between their expressions profile and prognosis in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) adult patients.

METHODS

The study involved 30 AML patients, 25 ALL patients, and 20 controls. Gene expression was analyzed using quantitative reverse transcriptase polymerase chain reaction (QRT-PCR).

RESULTS

In both AML and ALL groups, beclin-1 and MAB1LC3B expressions were significantly down-regulated (p < 0.001), while HIF-1α (p < 0.01) and Bcl-2 (p < 0.001) expressions were significantly up-regulated compared to the control group. HIF-1α fold expression was significantly negatively correlated with beclin-1 (p < 0.01). Moreover, decreased beclin-1 gene expression and increased HIF-1α gene expression were both associated with poor survival, supporting their pivotal role in the development and progression of acute leukemia.

CONCLUSIONS

Both Beclin-1 and HIF-1α could be considered as important biomarkers determinants of pathogenesis and survival in acute leukemia.

Synthesis, reactions and biological activity of some new thieno[2,3-f]-1,3-benzodioxoles

The reaction of 7-chlorothieno[2,3-f]-1,3-benzodioxole-6-carbonyl chloride (2) with some aromatic or heterocyclic amines gave the corresponding 6-(aryl or heterocyclyl) carbamoyl-7-chlorothieno [2,3-f]-1,3-benzodioxoles (3a-c, 4a, b and 5). Compound 2 was also reacted with potassium thiocyanate, ethanol or sodium azide to afford the isothiocyanto compound 6, the ester 7 and the acid azide 9, respectively. Hydrazinolysis of 7 gave the carbohydrazide 8. The compounds 6, 8 and 9 were used as precursors in the synthesis of the target heterocycles, 7-chlorothieno[2,3-f]-1,3-benzodioxoles substituted with a variety of moieties at position-6 (10-15, 17, 19-26, 28-31). Also, 2-methyl-1,3-dixolo[5,6][1]benzothieno[2,3-c]quinolin- 6(5 H)-one (33) was prepared. The antibacterial and antifungal activities of some selected compounds were also reported.

Synthesis and antimicrobial activity of pyrazolo[3',4':4,3]pyrido[6,5-c]pyridazine and thieno[2,3-c]pyridazine derivatives

4-Acetyl-5,6-diphenyl-2(H)pyridazine-3-one (1) was allowed to react with phenyl hydrazine to afford the corresponding hydrazone 2. Hydrazone 2 upon treatment with Vilsmeier's reagent gave pyrazolylpyridazine derivative 3, which was allowed to react with thiosemicarbazide and hydroxyl amine to give the corresponding thiosemicarbazone and oxime 4 and 5, respectively. Treatment of oxime 5 with Ac2O gave the pyrazolylpyridazine carbonitrile derivative 6. Compound 5 reacts with POCl3 to give the corresponding chloro compound 7. The chloro compound 7 was reacted with hydrazine hydrate or aniline to afford pyrazolopyridazodiazepine 9 or pyrazolopyridazopyridazine 10. When compound 1 was allowed to react with POCl3 the chloro derivative 11 resulted. This compound reacts with thiourea, piperidine or hydrazine hydrate to give compounds 12, 14 and 15, respectively. Compound 12 reacted with alpha-haloester or alpha-haloketone to give the thienopyridazines 13a and b, respectively. Most of the newly synthesized compounds were screened for fungicidal and bactericidal activity.

Synthesis and anti-microbial activity of some imidazo[1',2':5,6]pyrimido[4,5-c]pyridazines and related heterocycles

The synthesis of the title heterocycles was achieved using 3-amino-5,6-diphenylpyridazine-4-carbonitrile (4) as a starting material. This compound was converted into the corresponding 4-imidazolinyl derivative 5 which was then subjected to cyclization reactions to afford the title compounds.