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ObjectiveTo evaluate the effectiveness of a novel computerized quantitative analysis based on histopathological and computed tomography (CT) images for predicting the postoperative prognosis of esophageal squamous cell carcinoma (ESCC) patients.MethodsWe retrospectively reviewed the medical records of 153 ESCC patients who underwent esophagectomy alone and quantitatively analyzed digital histological specimens and diagnostic CT images. We cut pathological images (6000 × 6000) into 50 × 50 patches; each patient had 14,400 patches. Cluster analysis was used to process these patches. We used the pathological clusters to all patches ratio (PCPR) of each case for pathological features and we obtained 20 PCPR quantitative features. Totally, 125 computerized quantitative (20 PCPR and 105 CT) features were extracted. We used a recursive feature elimination approach to select features. A Cox hazard model with L1 penalization was used for prognostic indexing. We compared the following prognostic models: Model A: clinical features; Model B: quantitative CT and clinical features; Model C: quantitative histopathological and clinical features; and Model D: combined information of clinical, CT, and histopathology. Indices of concordance (C-index) and leave-one-out cross-validation (LOOCV) were used to assess prognostic model accuracy.ResultsFive PCPR and eight CT features were treated as significant indicators in ESCC prognosis. C-indices adjusted for LOOCV were comparable among four models, 0.596 (Model A) vs. 0.658 (Model B) vs. 0.651 (Model C), and improved to 0.711with Model D combining information of clinical, CT, and histopathology (all pConclusionQuantitative prognostic modeling using a combination of clinical data, histopathological, and CT images can stratify ESCC patients with surgery alone into high-risk and low-risk groups.

Currently, the incidence of esophageal squamous cell carcinoma (ESCC) in China is high and its prognosis is poor. To evaluate the prognosis of patients with ESCC, we performed computerized quantitative analyses on diagnostic computed tomography (CT) and digital histopathological slices. A retrospective study was conducted to assess the prognosis of ESCC in 153 patients who underwent esophagectomy, and the cohort was selected based on strict clinical criteria. Each patient had an enhanced CT image, and there were two imaging protocols for CT images of all patients. Each patient in the cohort also had a histopathological tissue slide after hematoxylin-eosin staining. Under an electron microscope, the tissue slide was scanned as an image of large size. We then performed quantitative analyses to identify factors related to the prognosis of ESCC on digital histological images and diagnostic CT images. For CT images, we used the radiomics method. For histological images, we designed a set of quantitative features based on machine learning algorithms, such as K-means and principal component analysis. These features describe the patterns of different cell types in histopathological images. Subsequently, we used the survival analysis model established using only CT image features as the baseline. We also compared multiple machine learning models and adopted a five-fold cross-validation method to establish a robust survival model. In establishing survival models, we first used CT image features to establish survival models, and the C-index from the Weibull Cox model on the test set reached 0.624. Then we used histopathlogical features to establish survival models, and the C-index from the Weibull Cox model on the test set reached 0.664, which was obviously better than CT's. Lastly, we combined CT image features and histopathological image features to establish survival models. The performance was better than that in the models built using only CT image features or histopathological image features, and the C-index from the regularized Cox model on the test set reached 0.694. We also proved the effectiveness of the quantified histopathological image features in terms of prognosis using the log-rank test. Histopathological image features are more relevant to prognosis than features extracted from CT images using radiomics. The results of this study provide clinicians with a reference to improve the survival rate of patients with ESCC after surgery. These results have implications for advancing the process of explaining the poor prognosis of esophageal cancer.

Background This study aimed to explore the significance of preoperative levels of squamous cell carcinoma antigen (SCC-Ag) and albumin on the cancer-specific survival (CSS) of patients with stage T1-3N0M0 in esophageal squamous cell cancer (ESCC). Methods The data of 308 patients who underwent esophagectomy between 1996 and 2011 were analyzed. SCC-Ag and albumin levels were measure 1 week before surgery. The optimal cutoff levels of SCC-Ag and albumin were determined using the X-Tile software, which were 1.0 μg/L and 39.8 g/L, respectively. The associations between SCC-Ag and albumin levels and clinicopathological characteristics were assessed using the χ2 test, Student’s t-test and Fisher’s exact test. Cox univariable and multivariable analyses were computed to identify SCC-Ag and albumin levels as independent prognostic factors related to the CSS of patients with ESCC. We used the Kaplan-Meier survival curve to determine the significance of SCC-Ag and albumin level on ESCC in the long-term follow-up. Results The 5-year CSS rate for the entire cohort was 65.0%. There was a significant difference in CSS between the low and high SCC-Ag level groups (hazard ratio [HR], 1.828, 95% confidence interval [CI], 1.203–2.778; P = 0.005). Patients with ESCC with low albumin level had a worse CSS than those with high albumin level (HR, 0.540; 95% CI, 0.348–0.838; P = 0.006). Patients with both high SCC-Ag and low albumin levels had worse 5-year CSS than patients with low SCC-Ag and high albumin levels (P Conclusions Preoperative serum SCC-Ag and albumin levels can predict survival in patients ESCC with stage T1-3N0M0. Patients with ESCC with high SCC-Ag and low albumin levels may have a poor survival outcome.

PURPOSE: To explore the postoperative prognosis of patients diagnosed with esophageal squamous cell carcinoma (ESCC) of stage T1-3N0M0 using a survival prognostic model (SPM). PATIENTS AND METHODS: Patients diagnosed with stage T1-3N0M0 ESCC from two cancer centers—Sun Yat-sen University Cancer Center (SYSUCC-A/ training cohort: N = 555), SYSUCC-B/ internal validation cohort: N = 241) and Henan Cancer Hospital (HNCH/ external validation cohort: N = 170)—that had undergone esophagectomy between 1995 and 2015 were enrolled in this study. The primary clinical endpoint was overall survival (OS). We have identified and integrated significant prognostic factors for OS by univariate and multivariate Cox regression methods applied in the training cohort to build a SPM that could be validated in the validation cohorts.RESULTS: The OS evaluation by the SPM was comparable in three cohorts (SYSUCC-A: C-index 0.654, SYSUCC-B: C-index 0.630, HNCH: C-index 0.688). Discretization of patients was done using a fixed survival score cutoff of 136.434 based on our SPM determined from the training cohort divided into low- and high-risk subgroups with stratified OS in the validation cohort (SYSUCC-A: hazard ratio [HR] 1.009, 95% confidence intervals [CI], 1.006–1.011, P < 0.001; SYSUCC-B: HR 1.009, 95% CI, 1.004–1.013, P ˂ 0.001; HNCH: HR 1.010, 95% CI 1.005-1.015, P = 0.0017). The 48-month OS in the low-risk subgroup vs. that in the high-risk subgroup was 80.8% vs. 60.9% for SYSUCC-A, 86.4% vs. 60.7% for SYSUCC-B, and 89.7% vs. 64.1% for HNCH. CONCLUSION: We have established and validated a novel SPM that can predict the OS for T1-3N0M0 ESCC patients and could help clinicians to detect subgroups of patients with poor prognosis.

Objective: To assess the postoperative prognosis of patients with stage IB non-small cell lung cancer (NSCLC), using a prognostic model (PM).Methods: Patients with stage IB of NSCLC from the two academic databases {the Surveillance, Epidemiology, and End Results [SEER-A, N = 1,746 (training cohort)], Sun Yat-sen University Cancer Center [SYSUCC, N = 247 (validation cohort)], and SEER-B (N = 1,745)} who had undergone lung surgery from 2001 to 2015 were enrolled. The primary clinical endpoint was cancer-specific survival (CSS). Covariate inclusion of prognostic indicators was carried out using a multivariable two-sided P < 0.05. We identified and integrated significant prognostic factors for survival in the training cohort to build a model that could be validated in the validation cohort. We used univariate analysis to evaluate the utilized ability of PM in the different races/ethnicities.Results: CSS discrimination in the PM was comparable in both the training and validation cohorts [C index = 0.66(SEER-A), 0.67(SYSUCC), and 0.61(SEER-B), respectively]. Discretization with a fixed PM cutoff of 291.5 determined from the training dataset yielded low- and high-risk subgroups with disparate CSS in the validation cohort (training cohort: hazard ratio [HR] 2.724, 95% confidence intervals [CI], 2.074–3.577; validation cohort: SEER-B HR 1.679, 95% CI, 1.310–2.151, SYSUCC HR 3.649, 95% CI 2.203–6.043, all P < 0.05). Our five-factor PM was able to predict CSS; 48-month CSS was 87% in the low-risk subgroup vs. 69% in the high-risk subgroup for the training cohort, while in the validation cohort, they were 80 vs. 73%(SEER-B) and 84 vs. 60% (SYSUCC), respectively. In addition, the results showed that PM with all unadjusted HR > 1 was a significant risk prognostic indictor in white men (P < 0.001), Chinese people (P < 0.001), and other races (P = 0.012).Conclusion: We established and validated a PM that may predict CSS for patients with IB NSCLC in different races/ethnicities, and thus, help clinicians screen subgroups with poor prognosis. In addition, further prospective studies and more cases from different regions are necessary to confirm our findings.

The incidence of esophageal squamous cell carcinoma (ESCC) in China is high and the prognosis is poor. Aimed to evaluate the ESCC, we investigated computerized quantitative analyses on diagnostic computed tomography (CT) and digital histopathological slices. A retrospective study with IRB approval was conducted to assess the prognosis of ESCCs in 158 patients who underwent esophagectomy. Every of them has 3D CT image and pathological hematoxylin-eosin staining tissue slide. We performed quantitative analysis on digital histology slices and diagnostic CT volumes. A total of 125 computerized quantitative features were extracted including 20 pathological image clustering (PIC) features and 105 CT features. Then we selected 45 CT features by correlation analysis and 5 PIC features by univariate survival analysis for preventing overfitting. Cox hazard model with L1 penalization was used for prognostic indexing. We compared three different prognostic indices in order to build a robust model: Model A: using CT features alone; Model B: using PIC features alone; Model C: using both CT and PIC features. For testing the model, we performed leave-one-out cross-validation for testing and we used the index of concordance(C-index) to access the accuracy of the prognostic model. The testing C-index values of Model A, B, C were 0.667, 0.601 and 0.711. The improvement of the final Model C is significant and it’s able to provide effective stratification. Quantitative prognostic modeling with joint information from clinical, histopathology, and diagnostic CT has the ability to stratify the patient well. Our prognostic model has potential to impact the perioperative care in the future clinical practice and improve the quality of individual life.

The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis) have a high medicinal value as a traditional Chinese medicine (TCM). Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC) method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS) method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC) method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently.

Objectives This study tested the relationship between preoperative serum C-reactive protein (CRP) levels and cancer-specific prognosis in patients with esophageal squamous cell carcinoma who have undergone curative resection. Methods We conducted a retrospective study on 961 patients with esophageal squamous cell cancer who underwent curative esophagectomy from 2006 to 2012 at the Sun Yat-sen University Cancer Center. Preoperative serum CRP levels were determined, and a cutoff value of 5.0 mg/mL was established. Propensity score matching (PSM) was performed to reduce the selection bias between patients with low CRP (≤ 5.0 mg/mL) and those with high CRP (> 5.0 mg/mL) levels based on age, tumor-lymph node-metastasis (TNM) stage, and tumor grade. The prognostic value of preoperative CRP levels was determined using life table, Kaplan–Meier, and Cox proportional hazards analyzes. Results In the unmatched cohort, the 3-year and 5-year survival rates were 57 and 53%, respectively, in patients with high preoperative CRP levels (> 5.0 mg/mL) and 68 and 56%, respectively, in those with low preoperative CRP levels (≤ 5.0 mg/mL). The difference in the survival rates of the 2 groups was significant (p = 0.004). Univariate survival analysis revealed that the preoperative CRP levels, TNM stage, tumor grade, drinking history, and anastomosis method were prognostic factors for overall survival (OS). Before conducting PSM, the low-CRP group had a lower age (p = 0.001), lower histological grade (p = 0.086), and lower TNM stage (p = 0.254). After PSM, 176 patients with low CRP levels and 176 of those with high CRP levels were enrolled in the analysis. In the matched cohort, the 3-year and 5-year survival rates were 56 and 50%, respectively, in patients with high preoperative CRP levels (> 5.0 mg/mL) and 68 and 56%, respectively, in those with low preoperative CRP levels (≤ 5.0 mg/mL). The difference in the survival rates between the low- and high-CRP groups was significant (p = 0.044). Multivariate analysis of the matched patients revealed that the TNM stage and preoperative CRP level were independent prognostic factors for OS. Conclusions A high preoperative CRP level (> 5.0 mg/mL) predicts worse survival prognosis in patients who have undergone curative resection for esophageal squamous cell cancer.

Four new sesquiterpenoids，including three nor-cinalbicane type sesquiterpenoids, named Jasminol A, G, H (1–3) and one eremophilene-type sesquiterpenoid, named Jasminol B (4) together with nine known compounds (5–13) were isolated from the stems of Jasminum officinale L. The structures of new compound were elucidated on the base of IR, HR-ESI-MS, 1D NMR, 2D NMR and DEPT analysis, and the absolute configurations were determined by single-crystal X-ray diffraction analysis. In addition, the anti-inflammatory activity of isolated compounds was evaluated using lipopolysaccharide (LPS)-induced murine macrophage RAW264.7, and compounds 1–4 exhibited a moderate inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 cells with IC50 values of 20.56 ± 1.31, 30.12 ± 0.89, 30.35 ± 2.72 and 31.60 ± 1.69 μM, respectively, and CC50 values >200 uM.

Background: Testicular cancer represents the most common malignancy in young adult men. In the current study, we sought to analyze and compare the prognostic value of lymph node ratio (LNR) as well as positive lymph node counts (LNC) to understand its clinical significance in testicular germ cell tumors. Methods: We employed eligibility criteria to recruit a total of 931 patients, with testicular cancer, from 2010 to 2015 from The Surveillance, Epidemiology, and End Results (SEER) database. We then used the X-Tile program to calculate LNR and LNC cutoff values and discriminate survival. We then calculated the overall and cancer specific survival rates and analyzed the association between LNR/LNC and clinical pathological characteristics using the χ2 test. Finally, we assessed the relationships between clinical pathological factors and patient survival using univariate Cox proportional hazard analysis. Results: Univariate analysis revealed a significant association between prognosis with age (HR, 5.169; 95% CI, 1.758-15.200; P = 0.003), AJCC stage (III vs I: HR, 9.298; 95% CI, 2.691-32.131; P < 0.001), M stage (HR, 7.897; 95% CI, 3.417-18.251; P < 0.001) and LNR (HR, 3.009; 95% CI, 1.275-7.098; P = 0.012). On the other hand, LNC (HR, 1.743; 95% CI, 0.687-4.420; P = 0.242) was not significantly associated with prognosis. Analysis of the association between LNR/LNC and clinical pathological characteristics showed that high LNR patients tended to have significantly larger tumor sizes (χ2 = 7.877, P = 0.005), as well as advanced T (χ2 = 13.195, P = 0.004), N ( χ2 = 86.775, P < 0.001), M (χ2 = 19.948, P < 0.001) and 7th AJCC (χ2 = 103.074, P < 0.001) stages. In addition, high LNC patients were significantly associated with T (χ2 = 8.799, P = 0.032), N (χ2 = 74.390, P < 0.001) and 7th AJCC (χ2 = 111.759, P < 0.001) stages. Conclusion: LNR was a better predictor for long-term prognosis and was closely associated with clinical pathological characteristics than LNC in patients with testicular germ cell tumors.

The stems of Dendrobium officinale Kimura et Migo (Dendrobii Officinalis Caulis) have a high medicinal value as a traditional Chinese medicine (TCM). Because of the limited supply, D. officinale is a high priced TCM, and therefore adulterants are commonly found in the herbal market. The dried stems of a closely related Dendrobium species, Dendrobium devonianum Paxt., are commonly used as the substitute; however, there is no effective method to distinguish the two Dendrobium species. Here, a high performance liquid chromatography (HPLC) method was successfully developed and applied to differentiate D. officinale and D. devonianum by comparing the chromatograms according to the characteristic peaks. A HPLC coupled with electrospray ionization multistage mass spectrometry (HPLC-ESI-MS) method was further applied for structural elucidation of 15 flavonoids, 5 phenolic acids, and 1 lignan in D. officinale. Among these flavonoids, 4 flavonoid C-glycosides were firstly reported in D. officinale, and violanthin and isoviolanthin were identified to be specific for D. officinale compared with D. devonianum. Then, two representative components were used as chemical markers. A rapid and reliable high performance thin layer chromatography (HPTLC) method was applied in distinguishing D. officinale from D. devonianum. The results of this work have demonstrated that these developed analytical methods can be used to discriminate D. officinale and D. devonianum effectively and conveniently.

Flow shear stress plays important roles in modulating differentiation of endothelial progenitor cells (EPCs). MicroRNAs are crucial for diverse cellular processes, but the expressions and functions of microRNAs in EPCs responding to mechanical stimuli remain unclear. We sought to determine the effects of microRNA-34a (miR-34a) and a novel target Forkhead box j2 (Foxj2) on shear stress-induced EPC differentiation. Human umbilical cord blood-derived EPCs were exposed to laminar shear stress of 15 dyn/cm 2 with parallel plate flow chamber system. Real time RT-PCR showed that shear stress significantly increased miR-34a expression, which was accompanied by the endothelial differentiation of EPCs. Whereas Foxj2, a putative target of miR-34a predicted by multiple algorithms, was suppressed in this process. Dual luciferase reporter assays, as well as miR-34a mimics and inhibitor treatment were used to confirm the interplay between miR-34a and Foxj2. Our results revealed an inverse correlation of miR-34a and Foxj2 expressions implicated in the endothelial differentiation of EPCs. MiR-34a contributed to this process by up-regulating the expressions of endothelial cell markers, and down-regulating smooth muscular cell markers. In addition, Foxj2 overexpression attenuated endothelial differentiation of EPCs, while Foxj2 siRNA had the opposite effect. These data suggested a unique mechanism that shear stress induces the expression of miR-34a, which targets to Foxj2 and promotes endothelial differentiation of EPCs. The results provide new insights into miR-34a/Foxj2 on shear stress-induced EPC differentiation.

A new simple Pd(memantine)2Cl2 complex was synthesized and characterized by 1H NMR, 13C NMR and X-ray single crystal structure determination. The Suzuki–Miyaura reaction of aryl bromides catalyzed by Pd(memantine)2Cl2 complex was investigated in air with different temperature. The high turnover numbers of 650,000 have been obtained in the reaction of 4-bromonitrobenzene with phenylboronic acid at 80 °C. At room temperature, the complex also showed high activity for Suzuki–Miyaura cross-coupling reaction of aryl bromides with a wide range of functional groups under air, and the turnover number of up to 99,000 was achieved. The catalytic system also gives good yields toward the reaction of several heteroaryl bromides with thiophenylboronic acid.

To decrease the computational complexity and improve the performance of channel estimation for underwater acoustic (UWA) sparse multipath channels, a sparse least square (SLS) channel estimation algorithm is proposed. The proposed algorithm combines advantages of both generalized akaike information criterion (GAIC) estimation and estimation using effective order of channel impulse response (CIR). Known pilot data is used to estimate effective order of CIR and then the position of taps of CIR is estimated. In order to adapt to the environment with low SNR and reduce the dimension of signal space, adaptive threshold is also used. Simulation results indicate that the proposed method has good performance of channel estimation and low complexity.

Common joint synchronization of timing and frequency algorithms based on training symbols are analyzed. Training symbols are discussed and then a new algorithm based on training symbol with special structure is proposed and applied in SC-FDE (Single Carrier Frequency Domain Equalization) systems. The proposed algorithm absorbs the advantages of the common algorithms and comparison between different algorithms shows that the proposed algorithm achieves better performance.

An efficient, general, one-pot, three-component procedure for the preparation of 3,5-disubstituted 1H-pyrazoles via condensation of substituted aromatic aldehydes, tosylhydrazine and terminal alkynes in toluene is reported. The reaction tolerates a variety of functional groups and sterically hindered substrates to afford the desired pyrazoles in yields of 67–91%.

A highly active catalyst system derived from PdCl2 and2,2′,6,6′-tetramethoxy-4,4′-bis(diphenylphosphanyl)-3,3′-bipyridine (P-Phos) has been developed for the Suzuki cross-coupling reaction of pyridylboronic acid with a variety of aryl halides in good to excellent yields, even in the presence of hindered and functional groups. In addition, P-Phos also exhibited high activity in the palladium-catalyzed Suzuki reaction of 2,6-dimethoxypyridylboronic acid in excellent yields with a fast rate. The steric and electronic effects of the P-Phos–palladium complex to this cross-coupling reaction were also discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The Pd-memantine complex (PCM) efficiently catalyzes the coupling of a wide range of aryl bromides with arylboronic acids at 80°C or at room temperature.

The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed Sonogashira reaction in the absence of copper and amine. The coupling of various aryl bromides and aryl chlorides with phenylacetylene gave moderate to excellent yields.

To study the relationship between two polymorphisms, Arg194Trp and Arg399Glu, of DNA repair gene X-ray repair cross-complementing group 1 (XRCC1) and the susceptibility of breast cancer in Chinese women.A case-control study with 698 histologically-confirmed female breast cancer cases and 813 cancer-free controls frequency-matched by age and residential area was conducted, and the genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. Logistic regression analysis was used to evaluate the odds ratios (ORs) and 95% confidence intervals (CIs) of XRCC1 Arg194Trp and Arg399Glu with susceptibility of breast cancer. A Meta-analysis was used to evaluate the association of Arg399Glu with breast cancer in Chinese women.The genotype frequencies of Arg/Arg, Arg/Trp, Trp/Trp, Arg/Trp + Trp/Trp of XRCC1 gene 194 locus were 48.81% (327/670), 39.85% (267/670), 11.34% (76/670), 51.19% (343/670) in cases and 48.80% (387/793), 41.99% (333/793), 9.21% (73/793), 51.20% (406/793) in controls. Compared to Arg/Arg, the adjusted ORs (95%CIs) were 0.98 (0.75 - 1.28), 1.17 (0.76 - 1.80), 1.09 (0.86 - 1.40). The frequencies of Arg/Arg, Arg/Trp, Trp/Trp, Arg/Gln + Gln/Gln of XRCC1 399 locus were 52.40% (349/666), 38.29% (255/666), 9.31%(62/666), 47.60% (317/666) in cases and 52.22% (412/789), 38.53% (304/789), 9.25% (73/789), 47.78%(377/789) in controls. Compared to Arg/Arg, the adjusted ORs (95%CIs) were 0.93(0.63 - 1.08), 0.96 (0.42 - 1.09), 0.91 (0.62 - 1.05). No significant associations were found between these two polymorphisms and breast cancer risk, also in subgroups stratified by menopause status, history of breast-feed, reproduction and taking oral contraceptives. The overall ORs (95%CIs) of 399 Arg/Trp + Trp/Trp vs Arg/Arg from Meta analysis was 0.97 (0.85 - 1.10).The XRCC1 Arg194Trp and Arg399Gln may not play an important role in the susceptibility of breast cancer in Chinese women.

A highly active catalyst system derived from PdCl2 and2,2′,6,6′-tetramethoxy-4,4′-bis(diphenylphosphanyl)-3,3′-bipyridine (P-Phos) has been developed for the Suzuki cross-coupling reaction of pyridylboronic acid with a variety of aryl halides in good to excellent yields, even in the presence of hindered and functional groups. In addition, P-Phos also exhibited high activity in the palladium-catalyzed Suzuki reaction of 2,6-dimethoxypyridylboronic acid in excellent yields with a fast rate. The steric and electronic effects of the P-Phos–palladium complex to this cross-coupling reaction were also discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)