No. Zerynth has been developed from scratch, thanks to the support of a Kickstarter Campaign. Following you can see a more detailed comparison between Zerynth and Micropython. 

  • Zerynth has a smaller footprint 
    60k-80k of flash, 3-5k ram versus 80k-280k of flash and 8k of ram for MicroPython (see here). Such a footprint is achieved by writing the VM from scratch and choosing to remove the compiler and the REPL  from the microcontroller; the Zerynth Uplinker allows to flash a minimal VM on the microcontroller once and subsequently add to it only the necessary drivers embedded in bytecode. Zerynth is Python even more tuned to micros than MicroPython is. Let’s say that Zerynth is a Micro MicroPython. 
  • Zerynth features (multiple) RTOS for multithreading 
    In Zerynth each Python thread is an RTOS thread managed by a priority aware real-time scheduler; in MicroPython, in our best knowledge, there is a custom round robin scheduler. In Zerynth the RTOS threads written in C can live along the VM allowing for a mixed C/Python real-time environment. 
  • Zerynth supports C-Python programming 
    Existing C code (or C object code) can be easily mixed with Python scripts without VM recompilation. For example, the Broadcom SDK for the Particle Photon is embedded in bytecode and uplinked to a running VM. Existing C code can be included in MicroPython too, but a VM recompilation is needed. 
  • Zerynth supports a subset of Python 3.4 and adds new embedded-friendly features 
    To make Zerynth suitable for microcontrollers constrained resources, support for generators, context managers, and full-fledged closures have been made optional (will be compiled into the VM if needed). Moreover, Zerynth has a new type, the shortarray, to handle 16-bit integer arrays. Also, Zerynth exceptions are lean and memory efficient, but still retaining the powerful debugging capabilities of tracebacks. 
  • Zerynth has a cross-platform IDE built on a command-line toolchain 
    Zerynth Studio takes away the burden of compiling the VM, of setting up various toolchains and tools (arm gccxtensa gccetc…) and gives an easy to use interface to code and debug embedded Python. For MicroPython no official IDE does exist. Zerynth is based on a command-line toolchain to ease and automate the integration of the Zerynth workflow for programmers who prefer other development environments.