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BACKGROUND: Myofascial pain syndrome (MPS) is recurrent local myofascial pain with various treatment methods. In recent years, extracorporeal shock wave therapy (ESWT) has attracted much attention, but its role still lacks systematic review. We included controlled clinical studies for meta-analysis to systematically evaluate the application effect of ESWT. METHODS: The English literature from PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science to October 2021 was searched by computer. After screening, the quality was evaluated by the PEDro (Physiotherapy Evidence Database) scale and analyzed by RevMan 5.4 software. RESULTS: A total of 571 patients were included in 8 studies. The MPS pain sites of 541 patients were in the neck and upper back, and only 30 patients had pain sites in the waist. Meta-analysis showed that the pain level after ESWT was lower than that after other treatment methods [mean difference (MD) =−1.34, 95% confidential interval (CI): −1.87 to −0.81, P

Lycopodium alkaloids (LAs) are the characteristic metabolites of club mosses. Chemical differences often exist in different specimens of a single plant species collected from different geographic origins. In this study, a preliminary LC-MS detection and dereplication analyses of alkaloidal constituents of Lycopodium cernuum var. sikkimense (Mull. Hal.) C.B. Clarke (LCVS2) collected from Fujian province led to the isolation and characterization of three undescribed LAs, lycocernuskines A-C, and six known cernuane-type LAs. The known compounds were previously isolated from the same plant species (LCVS1) collected from Chongqing, and so their dereplication in LCVS2 was accomplished based on their retention times (tR) and the quasi-molecular ion peaks in the LC-MS fingerprint. Chemical structures were identified by spectroscopic methods, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. Lycocernuskines A and B are the first two examples of C-12 hydroxylated phlegmarane-type LAs bearing a nitrone residue at the quinoline ring. The isolates were evaluated for their anti-AChE and neuroprotective effects.

A zirconium/nickel-mediated one-pot synthesis of ketones is reported. In the presence of Zn or Mn, Cp2 ZrCl2 was found to dramatically accelerate the coupling and suppress side product formation via an I→SPy displacement at the same time. Unlike Zn/Pd- and Fe/Cu-mediated one-pot ketone syntheses, the new method is effective for nucleophiles bearing OR or equivalent functional groups at the α-position. A mechanism comprising a nickel catalytic cycle, a zirconium catalytic cycle, and Zr→Ni transmetalation is proposed, and Cp2 ZrCl2 and/or low-valent Zr species are suggested to play crucial dual roles.

A unified, efficient, and scalable synthesis of the halichondrin class of natural products was reported. The newly developed Zr/Ni-mediated one-pot ketone synthesis was used to couple right halves with left halves, where Cp2ZrCl2 with Zn or Mn played a crucial role to accelerate the coupling reaction and, at the same time, suppress by-product formation. With use of a slight excess of the left halves, the desired ketones were isolated in 80~90% yields. Halichondrins were obtained from these ketones basically in two operations, i.e., desilylation and [5,5]-spiroketal formation. For the members in the halichondrins-A and -C sub-groups, however, an additional step was required to remove the protecting group at the polycycle, whereas for the members in the norhalichondrin sub-group, an additional step was used to hydrolyze the methyl ester at C53. The new synthetic route was successfully applied for a total synthesis of all the members in the homohalichondrin sub-group as well.

A highly convergent, stereocontrolled total synthesis of the architecturally complex marine sponge metabolite (-)-enigmazole A has been achieved. Highlights include an unprecedented late-stage large-fragment Petasis-Ferrier union/rearrangement, a multicomponent Type I Anion Relay Chemistry (ARC) tactic, and a dithiane-epoxide union in conjunction with an oxazole-directed stereoselective reduction.

An effective late-stage large-fragment union/rearrangement exploiting the Petasis–Ferrier protocol, in conjunction with multicomponent Type I Anion Relay Chemistry (ARC) to access advanced intermediates, permits completion of a convergent, stereocontrolled total synthesis of the architecturally complex phosphomacrolide (−)-enigmazole A (1).

The right halves of halichondrins A-C were synthesized by coupling the common C20-C37 building block 9 with the C1-C19 building blocks 10a-c, respectively. Catalytic, asymmetric Ni/Cr-mediated coupling was used for three C-C bond formations. For all cases, the stereochemistry was controlled with the Cr catalyst prepared from the chiral sulfonamide identified via the toolbox approach. For (3 + 4)-, (6 + 7)-, and (9 + 10)-couplings, the stereoselectivity of 28:1,40:1, and ∼20:1 was achieved by the Cr catalysts prepared from (S)-H, (S)-I, and (R)-L, respectively. Unlike the first and second couplings, the third coupling used the structurally complex nucleophile. It was demonstrated that the coupling efficiency was excellent even with the electrophile/nucleophile molar ratio = 1.0/1.1. In addition, the third coupling was achieved with the substrate bearing a free hydroxyl group. The products obtained in the Ni/Cr-mediated couplings were converted to the right halves of halichondrins A-C in excellent overall yields. The right halves of halichondrins A-C (1a-c) were synthesized in 28, 24, and 24 steps from commercial d-galactal in 13.4%, 21.1%, and 16.7% overall yield, respectively.